• Journal of applied mathematics & informatics
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• 제41권1호
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• pp.107-121
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• 2023

An epidemic infectious disease model consists of six compartments viz. Susceptible, Exposed, Infected, Quarantine, Recovered, and Virus with nonlinear saturation incidence rate is proposed to know the viral disease dynamics. There exist two biological equilibrium points for the model system. The system's local and global stability is done through Lyapunov's direct method about equilibrium points. The sensitivity analysis has been performed for the basic reproduction number and equilibrium points through the normalized forward sensitivity index. Sensitivity analysis shows that virus growth and quarantine rates are more sensitive parameters. In support of mathematical conclusions, numerical experimentation has been shown.

• Osong Public Health and Research Perspectives
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• 제5권4호
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• pp.187-192
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• 2014

Objectives: Measurement of the incidence of the human immunodeficiency virus (HIV) is very important for epidemiological studies. Here, we determined the recency period with the AxSYM avidity assay and the BED-capture enzyme immunoassay (BED-CEIA) in Korean seroconverters. Methods: Two hundred longitudinal specimens from 81 seroconverters with incident HIV infections that had been collected at the Korea National Institute of Health were subjected to the AxSYM avidity assay (cutoff = 0.8) and BED-CEIA (cutoff = 0.8). The statistical method used to estimate the recency period in recent HIV infections was nonparametric survival analyses. Sensitivity and specificity were calculated for 10-day increments from 120 days to 230 days to determine the recency period. Results: The mean recency period of the avidity assay and BED-CEIA using a survival method was 158 days [95% confidence interval (CI), 135-181 days] and 189 days (95% CI, 170-208 days), respectively. Based on the use of sensitivity and specificity, the mean recency period for the avidity assay and BED-CEIA was 150 days and 200 days, respectively. Conclusion: We determined the recency period to estimate HIV incidence in Korea. These data showed that the nonparametric survival analysis often led to shorter recency periods than analysis of sensitivity and specificity as a new method. These findings suggest that more data from seroconverters and other methodologies are needed to determine the recency period for estimating HIV incidence.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.165-168
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• 1999

To determine the effects of genetic and environmental influences on cell mediated immune (CMI) responses in broiler rabbits, contact sensitivity to 2,4-Dinitrochlorobenzene (DNCB) was assessed in three temperate broiler breeds of rabbits, namely Soviet Chinchilla, New Zealand White and Grey Giant. The feasibility of using the contact sensitivity to DNCB as a marker trait in selection for disease resistance was examined. There were highly significant differences between breeds (p<0.01) in initial skin thickness and contact sensitivities to DNCB at 24, 48 and 72 hours. Initial skin thickness was greatest in the Soviet Chinchilla breed (mean 2.2484 mm), and was significantly greater (p<0.01) in males (2.4963 mm) than in females (1.7846 mm) (p<0.01). Highest contact sensitivity to DNCB was in the New Zealand White breed with mean increase in skin thickness of 1.1884, 0.9072 and 0.5879 mm at 24, 48 and 72 hours post challenge respectively. Delayed type hypersensitivity (DTH) reaction to DNCB at 24 hours post challenge had a highly significant association (p<0.01) with the incidence of body mange in rabbits. The results indicated a lowered contact sensitivity to DNCB at 24 hours post challenge was associated significantly (p<0.01) with an increase in incidence and severity of body mange, suggesting its potential value as a marker. The correlation s among contact sensitivities at 24, 48 and 72 hours were positive and highly significant (p<0.01); correlations between initial skin thickness and contact sensitivities were negative and highly significant (p<0.01). Another notable significant correlation was between body weight and delayed type hypersensitivity at 24 hours indicating that an enhanced CMI might be associated with better growth rate and general wellbeing.

• 한국광학회지
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• 제32권3호
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• pp.126-132
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• 2021

본 논문에서는 특이 광 투과 현상 센서에서 보조 파장 홀 패턴에 입사되는 광원의 각도 조절을 통해 센서의 민감도를 측정 및 분석하여 이를 극대화할 수 있는 방법을 고안하였다. 입사파 광원을 평행화된 광원과 각도가 서로 다른 두 개의 집속화된 광원 총 3개의 광원을 시스템적으로 설계하여 서로 다른 각도로 보조 파장 홀 패턴에 입사되게 제작하였다. 그리고 증류수(n=1.333)와 굴절률 정합액(n=1.360, 1.380)을 사용하여 투과 스펙트럼을 측정하고 센서의 민감도를 계산한 결과 평행화된 광원을 사용하였을 때 센서의 민감도가 향상됨을 확인하였다.

• Wind and Structures
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• 제34권1호
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• pp.15-27
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• 2022

This work comes within the framework of the "Benchmark on the Aerodynamics of a Rectangular Cylinder" that investigates a rectangular cylinder of length-to-depth ratio equal to 5. The present study reports and discusses velocity fields acquired using planar Particle Image Velocitmetry for several angles of attack and Reynolds numbers. In particular, for a cylinder depth-based Reynolds number of 2 × 10⁴ and zero incidence angle, the flow features along the lateral (parallel to the freestream) upper and lower surfaces of the cylinder are reported. Using first and second order statistics of the velocity field, the main flow features are discussed, especially the size and location of the time-averaged flow structures and the distribution of the Reynolds stresses. The variation of the flow features with the incidence is also studied considering angles of attack up to 6°. It is shown that the time-averaged flow is fully detached for incidence higher than 2°. For an angle of attack of 0°, the effects of the Reynolds number varying between 5 × 10³ and 2 × 10⁴ are investigated looking at flow statistics. It is shown that the time-averaged location of the reattachment point and the shape and position of the time-averaged main vortex are mostly constant with the Reynolds number. However, the size of the inner region located below the time-averaged shear layer and just downstream the leading edge corner appears to be strongly dependent on the Reynolds number.

• 한국동물위생학회지
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• 제19권1호
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• pp.46-54
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• 1996

This study was perfomed to examine the distribution of causative agent of piglets diarrhea in eastern Chonnam province from February 1994 to March 1995. The causative agents of diarrhea were examined by bacterial culture test, parasitological test and serological test against PED, TGE and Rota. The 35 isolated E. coli were tested for antibiotic sensitivity. The results obtained were as follows. 1. The incidence of 81 piglets with diarrhea was most prevalent as 39.5% in the age of 2 to 4 weeks, compare to 34.6% in the age of 5 to 8 weeks and 16.0% under 1 weeks and 9.9 % in the age of 9 to 11 weeks after birth. 2. The incidence of 81 piglets diarrhea showed bacterial diarrhea(75.3%), viral diarrhea (35.8%) and parasitological diarrhea(18.5%). When compared the isolation frequency of each etiological agent, enteropathogenic E. coli was most prevalent as 55.5% in bacterial diarrhea, rotavlrus enteritis as 18.5% in viral diarrhea and trichuriasis as 13.6% in parasitological diarrhea. 3. The complicated infection of piglets was most prevalent as 41.7% in rotavirus enteritis with enteropathogenic E coli in 24 complicated piglets diarrhea. 4. In antibiotic sensitivity test, isolates showed moderatly resistance to Tobramycin, Amikacin, Imipenem, Trimethoprim/Sulfamethoxazole, Gentamicin, Ampicillin but sensitivty to Ticarcillin/K. The 30 E. coli isolate showed multiple drug resistances in 3 different antibiotics.

• Asian-Australasian Journal of Animal Sciences
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• 제28권12호
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• pp.1713-1720
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• 2015

The present work describes experiments undertaken to evaluate the usefulness of selected physicochemical indices of semen, cell membrane integrity and sperm chromatin structure for the assessment of boar semen sensitivity to processes connected with pre-insemination procedures. The experiments were carried out on 30 boars: including 15 regarded as providers of sensitive semen and 15 regarded as providers of semen that is little sensitive to laboratory processing. The selection of boars for both groups was based on sperm morphology analyses, assuming secondary morphological change incidence in spermatozoa as the criterion. Two ejaculates were manually collected from each boar at an interval of 3 to 4 months. The following analyses were carried out for each ejaculate: sperm motility assessment, sperm pH measurement, sperm morphology assessment, sperm chromatin structure evaluation and cell membrane integrity assessment. The analyses were performed three times. Semen storage did not cause an increase in the incidence of secondary morphological changes in the group of boars considered to provide sperm of low sensitivity. On the other hand, with continued storage there was a marked increase in the incidence of spermatozoa with secondary morphological changes in the group of boars regarded as producing more sensitive semen. Ejaculates of group I boars evaluated directly after collection had an approximately 6% smaller share of spermatozoa with undamaged cell membranes than the ejaculates of boars in group II ($p{\leq}0.05$). In the process of time the percentage of spermatozoa with undamaged cell membranes decreased. The sperm of group I boars was characterised with a lower sperm motility than the semen of group II boars. After 1 hour of storing diluted semen, the sperm motility of boars producing highly sensitive semen was already 4% lower ($p{\leq}0.05$), and after 24 hours of storage it was 6.33% lower than that of the boars that produced semen with a low sensitivity. Factors that confirm the accuracy of insemination male selection can include a low rate of sperm motility decrease during the storage of diluted semen, low and contained incidence of secondary morphological changes in spermatozoa during semen storage and a high frequency of spermatozoa with undamaged cell membranes.

• 수산해양교육연구
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• 제26권1호
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• pp.126-133
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• 2014

For boarding comfort and pleasant boarding sensitivity of passenger in passenger ship, there are a few methods such as motion sickness rate or MSI(Motion Sickness Incidence) to assess safety of passenger ship. To find out MSI or motion sickness rate of the training vessel Kaya of Pukyong National University, we use lots of various factors: sea condition, incident angle in main sail way, economic speed, calculation position of motion sickness, sea state, work place and reduce zone of ship. In this paper, we adopted Maxsurf Seakeeper program based on Strip Theory and carefully compared theoretical results with experimental results.

• The Korean Journal of Pain
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• 제20권1호
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• pp.26-30
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• 2007

Background: Epidural steroid injections (ESI) are a common treatment for spinal disorders. Previous research has shown that aspiration of the syringe is not a sensitive test for placement of an intravascular needle. Serious complications have been reported from injection of steroids and local anesthetics into the vascular space. In addition to safety concerns, the efficacy may decline with partial injection outside the desired epidural location. We hypothesized that incidence of vascular problems is increased in patients who undergo spine surgery compared with the patients who don't undergo spine surgery. We investigated the incidence of vascular problems during lumbosacral transforaminal ESI and we compared the difference of vascular problems between the patients who undergo spinal surgery and those patients who don't undergo spinal surgery. Methods: Two hundreds and three patients were consecutively recruited and they received 299 fluoroscopically guided lumbosacral transforaminal ESIs. Injection of contrast was performed under live dynamic fluoroscopy with using digital substraction analysis. The observed uptake pattern was classified into one of three categories: flashback, aspirated, and positive contrast with negative flashback and aspiration. Results: The vascular incidence rate was 20.4%. Transforaminal ESIs performed at S1 had avascular incidence rate of 27.8% compared with 17.7% for all the other lumbar injection sites. The sensitivity of spontaneous observation of blood in the needle hub or blood aspirate for predicting an intravascular injection in lumbar transforaminal ESIs was 70.4%. Conclusions: There is a high incidence of intravascular problems when performing transforaminal ESIs, and this is significantly increased in patients with previous spine surgery. Using a flash or blood aspiration to predict an intravascular injection is not sensitive therefore; a negative flash or aspiration is not reliable. Fluoroscopically guided procedures without contrast confirmation are prone to instill medications intravascularly. This finding confirms the need for not only fluoroscopic guidance, but also for contrast injection instillation when performing lumbosacral transforaminal ESIs, and especially for patients with previous spine surgery.

• 대한수의학회지
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• 제20권2호
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• pp.159-165
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• 1980

A total of 98 strains of Bordetella bronckiseptica isolated from pigs affected the infectious atrophic rhinitis(AR) during 1978 were surveyed for drug sensitivity to 26 chemotherapeutic agents, and minimum inhibitory concentration(MIC), incidence rate of resistant strain and resistant patern from the strains which were obtained from the different pig farm in Jeonnam province were examined. The results obtained are summarized as follows. 1. Most of the strains tested were resistant to Ampicillin (AB, PC), spiramycin(SPO, sulfa drugs (SD) (MIC:$400.0{{\mu}g/ml}$) and streptomycin(SM) (MIC:$200.0{{\mu}g/ml}$). Of the 75.0% of strains were also resistant to penicillin(PC) (MIC:$200.0{{\mu}g/ml}$) and of the 14.3 of strains were inhibited to grow to tetracycline(TC), chlortetracycline(CTC), oxytetracyc-line(OTC), erythromycin(EM), tylosin(TS), leucomycin (LM) and chloramphenicol (CP) (MIC:$6.25{{\mu}g/ml}$). On the other hand, most of the strains tested were inhibited to grow to kanamycin(KM), gentamycin(GM) neomycin(NM) (MIC:$25.0{{\mu}g/ml}$) and to colistin(CL) (MIC:$12.5{{\mu}g/ml}$). 2. Incidence rate of resistant strains to main chemotherapeutic agents was 100.0% of sulfa drugs, 96.4% of streptomycin, 85.7% of penicillin, tetracycline, chloramphenicol and erythromycin, 46.4% of gentamycin, 17.9% of colistin and 0.0% of kanamycin and nalidixic acid.