• Progress in Medical Physics
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• v.13 no.4
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• pp.195-201
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• 2002

Several investigators have presented the effects of external magnetic fields on the dose distributions for clinical electron and photon beams. We focus the low energy electron beam with more lateral scatter In this study we calculated the beam profiles for an clinical electron beam of 6 MeV with longitudinal magnetic fields of 0.5 T-3.0 T using a Monte Carlo code. The principle of dose enhancements in the penumbra region is to deflect the laterally scattered electrons from its initial direction by the skewness of the laterally scattered electrons along the direction of magnetic field lines due to Lorentz force under longitudinal magnetic field. To discuss the dose enhancement effect on the penumbra area from the calculated results, we introduced the simple term of penumbra reduction ratio (PRR), which is defined as the percentage difference between the penumbra with and without magnetic field at the same depth. We found that the average PRR are 33%, and 49% over the depths of 1.5 cm, 2.0 cm, and 2.4 cm for the magnetic fields of 2.0 T and 3.0 T respectively. For the case of 0.5 T and 1.0 T the effects of magnetic filed were not observed significantly. In order to obtain the dose enhancement effects by the external magnetic field, we think that its strength should be more than 2 T approximately. We expect that the PRR would be saturated to 50-60% with magnetic fields of 3 T-5 T As a result of these calculations we found that the penumbra widths can be reduced with increased magnetic fields. This Penumbra reduction is explained as a result of electron lateral spread outside the geometrical edges of the beam in a longitudinal magnetic field. This means that the electron therapy benefits from the external magnetic fields.

• Journal of the Korean Mathematical Society
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• v.50 no.5
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• pp.1105-1127
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• 2013

Let C[0, $t$] denote the function space of real-valued continuous paths on [0, $t$]. Define $X_n\;:\;C[0,t]{\rightarrow}\mathbb{R}^{n+1}$ and $X_{n+1}\;:\;C[0,t]{\rightarrow}\mathbb{R}^{n+2}$ by $X_n(x)=(x(t_0),x(t_1),{\ldots},x(t_n))$ and $X_{n+1}(x)=(x(t_0),x(t_1),{\ldots},x(t_n),x(t_{n+1}))$, respectively, where $0=t_0 <; t_1 <{\ldots} < t_n < t_{n+1}=t$. In the present paper, using simple formulas for the conditional expectations with the conditioning functions $X_n$ and $X_{n+1}$, we evaluate the $L_p(1{\leq}p{\leq}{\infty})$-analytic conditional Fourier-Feynman transforms and the conditional convolution products of the functions, which have the form $fr((v_1,x),{\ldots},(v_r,x)){\int}_{L_2}_{[0,t]}\exp\{i(v,x)\}d{\sigma}(v)$ for $x{\in}C[0,t]$, where $\{v_1,{\ldots},v_r\}$ is an orthonormal subset of $L_2[0,t]$, $f_r{\in}L_p(\mathbb{R}^r)$, and ${\sigma}$ is the complex Borel measure of bounded variation on $L_2[0,t]$. We then investigate the inverse conditional Fourier-Feynman transforms of the function and prove that the analytic conditional Fourier-Feynman transforms of the conditional convolution products for the functions can be expressed by the products of the analytic conditional Fourier-Feynman transform of each function.

• Korean Journal of Organic Agriculture
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• v.18 no.3
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• pp.347-361
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• 2010

This study was carried out to investigate the effects of wormwood (Artemisia sp.) addition on the growth performance, nutrients utilization and abdominal fat deposition of broiler chickens. Two hundred twenty five and two-day old Arboracre strain male commercial broiler chicks were distributed to 5 treatments with wormwood supplementation levels; C(O%), $T_1$ (1%), $T_2$ (3%), $T_3$ (5%), and $T_4$ (10%) and with 3 replications each with 5 birds for five weeks. Body weight gain during the experiment was improved in $T_1$ (1723.0g) compared with that of $T_3$ (1557.7g) and $T_4$ (1450.7g) (P<0.05). Feed intake was significantly (P<0.05) increased as the levels of wormwood addition increased (C: 2653.8g, T1: 2852.0, $T_2$: 2900.3, $T_3$: 2900.7g, T4: 2954.7g). Feed conversion rate (feed/gain) was significantly (P<0.05) increased as the levels of wormwood addition increased (C: 1.55, $T_1$: 1.66, $T_2$: 1.70, $T_3$: 1.86, $T_4$: 2.04). The days reaching to 2.0kg of body weight were expected to be 43.2 days in control, whereas those of group T1 were reduced to 42.6 days by 0.6 day from control. Nutrient utilization and abdominal fat deposition in the experiment were significantly decreased (P<0.05) and small intestine contents in the broilers was significantly increased (P<0.05) as the levels of wormwood addition increased. Therefore, although there was no significant improvement for the performance of broiler chickens with the dietary supplementation of wormwood meal, less than 1% addition of wormwood to broiler diets might have beneficial for human health by reducing the abdominal fat deposition of the broiler chicknens.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.298-302
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• 2006

A number of field experiments were conducted to assess the role of combined application of nitrogen and sulfur to increase the seed and oil yield of nonnodulating soybean (Glycine max (L) Merr.) cv. PK-416 $(V_1)$ and cv. PK-1024 $(V_2)$. Six combinations of N and S in three replicates each were used for this purpose i.e. $0\;S+23.5kg\;N\;ha^{-1}(T_1);\;0\;S+23.5+20kg\;N \;ha^{-1}(T_2);\;40\;S+23.5kg\;N\;ha^{-1}(T_3);\;40\;S+23.5+20kg\;N\;ha^{-1}(T_4);\;20+20\;S+23.5kg\;N\;ha^{-1}(T_5);\;20+20\;S+23.5+20kg\;N\;ha^l(T_6)$. Nitrate reductase (NR) and ATP-sulphurylase activities in the leaves were measured at various growth stages as the two enzymes catalyze the rate limiting steps of the assimilatory pathways of nitrate and sulphate, respectively. The activities of these enzymes were strongly correlated with seed yield. The higher seed, oil and protein yields were achieved with the treatment $T_6$ in both the cultivars due to optimization of NR activity and ATP-sulphurylase activity, as these parameters were influenced by N and S assimilation. Any variation from this combination was observed to decrease the activity of these enzymes resulting in reductions in the seed, oil and protein yield of soybean.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.325-337
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• 2003

This study was designed to determine the distribution of trans fatty acids (tFAs) isomers of Processed foods commonly consumed in Korea. The tFAs positional isomers were analyzed using GC/MS spectrometer with HP-23 cis/trans FAME, capillary column (50m $\times$ 0.20 mm, id., 0.2 ${\mu}{\textrm}{m}$ film thickness) for 41 food samples. TFAs isomers were identified by comparing retention time with standards and GC/MS spectrum. In margarines, the content of tFAs ranged from 4.0% to 25.16% and the most abundant positional isomer of tFAs was C18:1 $\Delta$9t. In oils and fats, lards contained higher levels of tFAs (5.70~16.54%) than shortenings (6.77~10.55%). Shortenings contained higher levels of C18:1 $\Delta$9t (3.1~5.1%) than lard (1.6~4.3%), but corn oils had no tFAs. In seasonings, mayonnaise had no C16:1 $\Delta$9t, whereas C18:3t was detected. The content of tFAs in confectioneries was wide (16.20~52.16%). Among them, instant popcorns contained the highest amount of tFAs. Milk and dairy products showed even distribution of tFAS such as C18:1t, C18:2t, and C18:3t. Predominant tFAS isomer of condensed milk and ice cream was C16:1 $\Delta$9t. Frozen french fries and fried chicken contained higher levels of C18:1$\Delta$9t (9.4%), whereas grilled pork (jowl) had no C18:1 $\Delta$9t. The amount of tFAs per serving size was the highest in popcorn, followed by frozen pizza, frozen french fries, fried chicken, and bakeries.

• Journal of Aquaculture
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• v.11 no.2
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• pp.231-240
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• 1998

Tetraselmis is widely used as a live food because of its easy handling, high nutrient, large size and wide tolerant range of temperature and salinity. In order to find the optimum Tetraselmis species for mass culture in Korea, five species of this microalgae were examined on size, optimum culture condition ${\textperthousand}$s, $^{\circ}C.$) and nutrient composition. The results obtained were as follows: Among five species of Tetraselmis, T. sp.(Haeundae) was the largest(major axis $17.6{\pm}1.87^{\mu}$m, mean cell volume 727${\mu}$m), and T. sp. (China) the smallest (major axis $14.6{\pm}1.46^{\mu}$m, mean cell volume 625m). Tetraselmis was very eurythermal and euryhaline species. But optimum temperature and salinity for growth were 24~$30^{\circ}C.$ and 27~30${\textperthousand}$, respectively. Among five species of Tetraselmis, T. sp. (China) seemed to be the most tolerant of high temperature over $30^{\circ}C.$, and T. tetrathele of low temperature below $6^{\circ}C.$. In culture density, T. suecica showed the highest growth rate among the among the five species. The cell density of this microalgae attained to $141{\times}10^4$cells/ml at $24^{\circ}C.$ and 30${\textperthousand}$ within 7 days. In chemical composition, crude protein amount was the highest in T. suecica (44.50%), and crude lipid amount it T. sp. (Haeundae, 7.13%). Total essential amino acid amount was the highest in T. sp. (Haeundae, 50.4%) and total polyunsaturated amount in T. sp. (China, 11.7%) The results on growth and chemical composition of five species of Tetraselmis indicated that T. suecica seemed to be the most suitable species for mass culture in Korea.

• Tuberculosis and Respiratory Diseases
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• v.41 no.6
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• pp.616-623
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• 1994

Objectives: Careful evaluation about mediastinal involvement is important in the management of patients with non-small cell lung cancer. Invasive staging procedure such as mediastinoscopy is advocated because of the unreliability of noninvasive staging methods such as CT, MRI. We compared differences between pre- and postoperative staging in non-small cell lung cancer without lymphadenopathy on CT scan and investigated the methods for more accurate preoperative staging. Methods & Results: 1) Records of a total of 41 patients with preoperative $T_{1-3}N_0M_0$ non-small cell lung cancer were reviewed and the histologic types of tumors were squamous cell carcinoma in 32 cases, adenocarcinoma in 6 cases and large cell carcinoma in 3 cases. Twenty-four cases were central lesions and seventeen cases were peripheral lesions. 2) Among the 32 cases with preoperative $T_2$, 2 cases were identified postoperatively as $T_3$ with invasion of chest wall and among 6 cases with preoperative $T_3$, 1 case was identified postoperatively as $T_4$ with invasion of aorta and pulmonary arteries. 3) After the operation of 35 cases with $T_{1-2}$, 5 cases were $N_1$ and 3 cases were $N_2$ postoperatively. After the operation of 6 cases with $T_3$, 2 cases were $N_1$ and 3 cases were $N_2$ postoperatively. Preoperative $T_3$ showed more intrathoracic lymph node metastases and higher $N_2/N_1$ involvement ratio than preoperative $T_{1-2}$. 4) Complete surgical resections were done in 34 out of 41 cases. Incomplete resection were done in all postoperative $N_2$ tumors. Conclusion: Invasive staging procedures such as mediastinoscopy should be considered in the case of preoperative $T_3$ non-small cell lung cancer even though mediastinal lymphadenopathy is not recognized on the CT scan of the chest.

• The Magazine of the IEIE
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• v.28 no.2
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• pp.90-104
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• 2001

최근까지 동물 또는 사람이 극저주파 전자기장에 평생 또는 여러 세대에 걸쳐 노출되었을 경우, 나타나는 생체영향에 관한 연구는 거의 없다. 본 연구에서는 마우스에 60Hz 전자파를 1세대부터 3세대까지 지속적으로 노출시켜 나타나는 영향을 실험하였다. 실험동물은 5주령인 BALB/c 마우스를 1주일간 적응시킨 후 사용하였다. 실험군은 5kV/m, 30kV/m, 0.5mT 그리고 1.5mT의 4개군으로 나누었으며, 대조군은 1군으로 실험하였다. 생후 6주부터는 위에서 정해진 양의 전자파를 20-22주간 지속적으로 실험동물에 조사하고 동일조건의 암수 마우스를 교미시켰으며, 임신 후에도 사망 또는 부검시까지 동일한 조건으로 계속 조사하였다. 2세대와 3세대는 임신적부터 사망 또는 부검시까지 동일한 조건으로 계속 조사하였다. 1, 2 그리고 3세대 마우스들은 질병에 의한 사망 직전 또는 생후 46주, 66주 그리고 생후 49주에 부검한 뒤, 혈액학적 및 생화학적 검사 그리고 조직병리학적 검사를 실시하였다. 2세대 태아에서는 조기사망(early fetal death), 성장기사망(late fetal death) 그리고 뇌노출(excencephaly) 및 선천성 심장기형을 포함하는 선천이상이 발견되었는데, 이는 대조군에 비해 2-4배 높았다. 1, 2세대에서는 생식기인 고환(testis)과 난소(ovary)의 무게가 감소하였으나 2세대에서는 아무런 변화를 보이지 않았다. 실험군인 30kV/m, 0.5mT 그리고 1.5mT 전 실험군인 30kV/m, 0.5mT 그리고 1.5mT 전자파에 노출된 1세대와 2세대 마우스에서는 프종(lymphoma), 선암종(adenocarcinoma), 기저상피세포증(basal cell epithelioma), 편평상 피두유종(squamous papilloma) 그리고 선종(adenoma) 등이 발견되었으나, 3세대에서는 발견되지 않았다. 60Hz 전자파는 태아 및 생식기에 영향을 미치고, 또한 종양을 유발할 가능성이 있다. 그러나 3세대는 전자파 환경에 점차 적응을 하는 것으로 보인다. 그러나 몇몇 국제기구에서 정하여 놓은 안전한계치의 전자파가 생체에 장기간 노출되었을 경우에 나타날 수 있는 생체영향을 확인하기 위해서는 많은 연구가 필요하다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.48-54
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• 1987

To search for the optimal nitrogen application method for the machine transplanting to Dongjinbyeo, compared to conventional method, in the various methods of nitrogen split application at different growth stages of rice plant. This experiment was performed at Honam Crop Experiment Station, in 1985 year. The results were as followed; the nitrogen contents of leaf blade was the highest at maximum tillering stage under the conventional method and reduction division stage under the nitrogen top-dressing at panicle initiation and 5 times split application of nitrogen for the whole rice growth stages. CGR, RGR and NAR after heading was highest under 5 times split application of nitrogen for the whole rice growth stages. Relationships between CGR and NAR, NAR and RGR, CGR and RGR showed the positive correlation significantly at each rice growth stage, respectively, and showed more high correlation according to further rice growth stages. The degree of contribution of CGR to rice grain yield was the highest at 20 days after heading. Rice grail: yield was higher under top-dressing of nitrogen at panicle initiation and basal application (30%) + 4 times equal dispensing top-dressing after basal application of nitrogen than conventional method.

• Pediatric Infection and Vaccine
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• v.7 no.1
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• pp.143-151
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• 2000

Purpose : The accuracy of bacteriologic diagnosis of beta-hemolytic streptococcal pharyngotonsillitis depends on the degree of carrier rate in that area where the throat swabs are obtained and the evaluation of serological T typing as an epidemiologic marker is important to understand epidemiology of streptococcal infection. The purpose of this study is to know the carrier rates of group A streptococcus in normal children form four different areas and to find out the epidemiologic characteristic in distribution of the serotypes for 3 years. Method : Throat swabs were obtained from the tonsillar fossa of normal school children in four different areas(Uljin, Seoul, Osan, Kunsan) from March to May 1996, in Uljin in April 1997, and in Uljin in April 1998. The samples were plated on a 5% sheep blood agar plate and incubated overnight at $37^{\circ}C$ before examination for the presence of beta-hemolytic colonies. All isolated beta-hemolytic streptococcus were grouped and serotyped by T agglutination. Results : The carrier rate of beta-hemolytic streptococci and group A streptococci in 1996 were 27.6%, 18.6% at Uljin; 16.4%, 2.7% at Seoul; 33.0%, 26.0% at Osan; 20.0%, 12.3% at Kunsan, respectively. Among 1,192 normal school children from 4 different areas, we obtained 179 strains of group A streptococci. Fifty two percent of the strains were typable by T agglutination in 1996. Common T-type in 1996 were NT, T1, T3, T2 at Uljin; T12, T25 at Seoul; NT, T6, T28 at Osan; T25, T4, NT, T5 at Kunsan, in decreasing order, respectively. At Uljin, T1, T3, T25 accounted for 69% of strains in 1996, T1, T12, T25 accounted for 70% in 1997, and T12, T4 accounted for 88% in 1998. Conclusion : Higher carrier rates were found in Uljin and Osan, where there are a lower population density with scanty of medical facilities compared with another areas. We supposed that low carrier rates is likely to be related to antibiotic abuse or some epidemiologic factor. The periodic and seasonal serotyping analysis is important in monitoring and understanding the epidemiologic patterns of group A streptococci.