• 제목/요약/키워드: AT&T

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고린(高燐) 활용성 토마토 항 염분 특성 (Salt tolerance in phosphorus efficient tomato (Lycopersicon esculentum Mill.))

  • 이동희
    • 한국환경농학회지
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    • 제17권1호
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    • pp.34-38
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    • 1998
  • 고율의 인활용성을 보이는 토마토 품종의 항염분 특성을 검증하기 위하여, 염분이 첨가된 배양액을 이용한 수경 재배를 실시하였다. 항염분성의 검증은 인산활용도가 높은 것으로 알려진 품종(T9과 T8)의 생육을 비인산 효율성 품종인 T5의 생육과 비교하여 실시하였다. 본 실험에 이용된 염분의 농도는 0, 1, 5, 10 g/L 이다. 0, 1g/L의 염분 농도에서는 두 집단 간의 유의성이 발견되지 않았다. 그러나 5, 10 g/L의 염분 농도에 있어서 T9과 T8의 생육은 T5와 비교하여 생물 및 건물 무게, 기공의 저항도, 지상 부 발달도 부문에 있어 유의성있게 앞선 것으로 나타났다. 반면, 나트륨, 인, 질소, 칼륨의 식물조직내의 농도는 품종간 차이가 없는 것으로 나타났다. 본 연구결가는 고 인 활용성 토마토 품종은 비 인효율성 품종에 비해 염분에 대한 저항성이 높은 것으로 판단된다.

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AT-DMB 시스템 환경에서 DAB 서비스를 위한 간섭분석 (Interference Analysis for DAB Service on the Advanced T-DMB System Environment)

  • 주상임;김영재;김경석;조주필
    • 한국인터넷방송통신학회논문지
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    • 제15권6호
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    • pp.51-59
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    • 2015
  • AT-DMB 시스템은 다른 디지털 방송 시스템에 비해 채널 대역폭 대비 데이터 전송 용량이 작은 T-DMB 시스템을 개선하기 위해 개발된 디지털 멀티미디어 방송 기술이다. 이 시스템은 계층변조 기술이 적용되어 기존 T-DMB의 데이터 전송 용량보다 최대 2배까지 증가시킬 수 있어 T-DMB보다 고품질의 비디오 서비스를 제공하거나, 더 많은 수의 방송 서비스를 전송할 수 있다. 따라서 기존 T-DMB 환경 기반에서 DAB 시스템의 도입을 위해 수행된 선행 연구들에 비해 AT-DMB 환경에서 DAB 시스템의 도입 연구를 다루는 것이 유리할 것이다. 이에 본 논문에서는 증가된 전송 데이터 용량을 가진 AT-DMB 시스템의 송신 환경에서 DAB 서비스를 제공하기 위한 방송망의 설계안을 제안하고, 이를 검증하기 위해 간섭분석을 수행하였다.

Effects of Spraying Illite and Zeolite on Litter Quality, Microflora, and Footpad Dermatitis in Broiler Litter

  • Sehyun Park;Jihwan Lee;Dongcheol Song;Seyeon Chang;Jaewoo An;Kyeongho Jeon;Hyuck Kim;Jinho Cho
    • 한국가금학회지
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    • 제50권4호
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    • pp.273-282
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    • 2023
  • A total of 192 one-day-old Ross 308 broilers (initial body weight: 31.30±0.41 g) were used in this experiment for 28 days. Treatments were as follows: basal rice husk (CON), rice husk + 1% illite (T1), rice husk + 1% zeolite (T2), and rice husk + 0.5% illite + 0.5% zeolite (T3). The percentage of illite and zeolite was calculated on a weight of litter. Each treatment had four replicates, with 12 birds per pen. Each pen was provided with 5 kg of rice husk as litter. Litter moisture content was significantly decreased (P<0.05) in the T1, T2, and T3 groups compared to CON group at week 4. In litter nitrogen, the T1 group showed significantly lower (P<0.05) litter nitrogen content than the other groups at weeks 1, 2, and 3. Also, the T3 group showed a significantly lower (P<0.05) litter nitrogen content than the CON and T2 groups at weeks 2 and 3. The counts of E. coli in the litter were significantly decreased (P<0.05) in the T1 group compared to the CON group at weeks 2 and 3. Moreover, the counts of Salmonella in the litter were significantly decreased (P<0.05) in the T1 group compared to the CON group at week 4. The FPD score significantly decreased (P<0.05) in the T1 group compared to the CON group. In conclusion, spraying illite could be an ideal way to improve litter quality and decrease FPD in broilers.

THYROID HORMONES AND TESTOSTERONE IN SHEEP AGE RELATED PROFILES OF SERUM THYROXINE, TRI-IODOTHYRONINE AND TESTOSTERONE IN KAGHANI, RAMBOUILLET AND KAGHANI × RAMBOUILLET SHEEP

  • Ahmad, M.M.;Mughal, M.R.;Bari, A.;Khan, M.I.;Shahab, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권1호
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    • pp.101-106
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    • 1992
  • Secretory patterns of serum tri-iodothyronine, thyroxin and testosterone were analysed by specific radioimmunoassay in Kaghani (n = 42), Rambouilet (n = 42) and Kaghani ${\times}$ Rambouillet (n = 42) male sheep to determine age and breed related changes. Animals were examined at 1-2 wk, 8, 10, 12, 20, 22 and 24 months of age (n = 6/age group). All animals were maintained under standard conditions of feeding and management. $T_3$ and $T_4$ concentrations were maximal (p < 0.01) in 1-2 wk old lambs of all breeds studied ($207.4{\pm}14.9-276.8{\pm}20.4ng/dl$ and $5.76{\pm}0.3-7.23{\pm}0.9{\mu}g/dl$, respectively). For all the breeds, concentrations of $T_3$ declined markedly (p < 0.01) at 8 month of age and then varied in a narrow range ($44.5{\pm}14.0-87.0{\pm}4.8ng/dl$) up to the age of 24 month. While, serum $T_4$ concentrations decreased (p < 0.01) to nadir ($0.97{\pm}0.1-1.43{\pm}0.3{\mu}g/dl$) at 10 months of age in all the 3 breeds. Afterwards, $T_4$ levels increased gradually and attained a small peak at 20 months before declining again at 22 and 24 months of age. Serum $T_3$ and $T_4$ concentrations were correlated significantly (p < 0.05) and their ratio was constant at all ages in the different breeds. Age significantly (p < 0.01) influenced the secretion of testosterone in the breeds examined but the breed differences were comparable. Mean serum concentrations of testosterone were low from 1-2 wk to 10 months of age in the Kaghani, Rambouillet and Kaghani ${\times}$ Rambouillet animals. Peak testosterone levels were noted in the 12 months old Kaghani ($1.75{\pm}0.4ng/ml$), Rambouillet ($1.30{\pm}0.2ng/ml$) and their $T_3$ cross animals ($1.16{\pm}0.08ng/ml$). Mean testosterone levels, thereafter, decreased at 20 months and then at 22 and 24 months remained variable but higher than observed at 1-2 wk -10 months of age. The findings of the present study indicate a significant influence of age but not of breed on the peripheral concentrations of thyroid hormones and testosterone. Serum concentrations of $T_3$ and $T_4$ were not related to testosterone levels. High thyroid secretory activity observed at prenatal phase of development may play an important role in preparing the lambs to extrauterine environments.

Detection of Toxoplasma gondii Infections using Virus-Like Particles Displaying T. gondii ROP4 Antigen

  • Kim, Min-Ju;Mao, Jie;Kang, Hae-Ji;Chu, Ki-Back;Quan, Fu-Shi
    • Parasites, Hosts and Diseases
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    • 제59권6호
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    • pp.565-572
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    • 2021
  • Toxoplasma gondii ME49 infections are typically diagnosed by serological tests. However, serological diagnosis of RH strain-induced toxoplasmosis remains unknown. In order to develop seradiagnosis of above 2 kinds of infections, we generated recombinant virus-like particles (VLPs) displaying the T. gondii rhoptry protein 4 (ROP4) and evaluated their potential in T. gondii ME49 or RH strain infection diagnostics. Mice were orally infected with either the tachyzoites of T. gondii (RH) or cysts of T. gondii (ME49) at various dosages, and sera were collected at regular intervals. ELISA-based serological tests were performed to assess IgG, IgM, and IgA antibody responses against ROP4 VLP antigen and tissue lysate antigen (TLA). Compared to TLA, IgG, IgM, and IgA levels to ROP4 VLP antigen were significantly higher in the sera of T. gondii RH-infected mice 1 and 2 week post-infection (PI). T. gondii-specific IgG antibody was detected at 1, 2, 4, and 8 week PI in the T. gondii ME49-infected mice with infection dose-dependent manner. These results indicated that the ROP4 VLP antigen was highly sensitive antigens detecting T. gondii RH and ME49 antibodies at an early stage.

라인강 유량의 추계학적 수문분석에 관한 연구 (네덜란드의 Lobith지점을 중심으로) (The Stochastic Hydrological Analysis for the Discharge of River Rhine at Lobith (For River Rhine at Lobith in the Netherlands))

  • 최예환
    • 한국농공학회지
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    • 제23권4호
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    • pp.46-52
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    • 1981
  • The aim at this study has the stochastic hydrological analysis for the annual mean discharge and monthly discharge which were observed at Lobith of River Rhine in the Netherlands from 1901 to 1972. After this study was analysed by computer IBM 370 and Hewlett Parkard 9800, the results were as follows; 1.When 72 data was divided into two groups of subsample data as 36 data, they do not have their properties to be non-homogeneous and inconsistent due to F-test and t-test. 2.The credit limits of the serial correlation coefficient was fluctuated $\pm$0. 231 which was shown in Fig. 3. at significant level 99% by Anderson's test. 3.The correlogram at short term was shown to be no short-term persistence as Fig. 3. 4.Since the correlogram at long term has displayed that Hurst's coefficient was 0.6144 between 0.6 and 0.7, it was to be no long-term persistence. 5.The stochastic model with annual discharge of this River Rhine was shown with $\chi$t=2195+483. 8 $\varepsilon$t as $\chi$t=$\mu$+oet and $\varepsilon$t=$_1$ø$\varepsilon$t-$_1$+ζt where t=1,2,3,..., ζt is an independent series with mean zero and variance (1-ø2), $\varepsilon$t is the dependent series, and 4' is the parameter of the model. 6.The serial correlation coefficient of monthly discharge was explained as $\chi$$_1$ = 0.34 . sin(6-$\pi$t+$\pi$) as Fig.4. and the River Rhine has no large fluctuation and smoothly changed during that time.

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Ultrashort Echo Time MRI (UTE-MRI) Quantifications of Cortical Bone Varied Significantly at Body Temperature Compared with Room Temperature

  • Jerban, Saeed;Szeverenyi, Nikolaus;Ma, Yajun;Guo, Tan;Namiranian, Behnam;To, Sarah;Jang, Hyungseok;Chang, Eric Y.;Du, Jiang
    • Investigative Magnetic Resonance Imaging
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    • 제23권3호
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    • pp.202-209
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    • 2019
  • Purpose: To investigate the temperature-based differences of cortical bone ultrashort echo time MRI (UTE-MRI) biomarkers between body and room temperatures. Investigations of ex vivo UTE-MRI techniques were performed mostly at room temperature however, it is noted that the MRI properties of cortical bone may differ in vivo due to the higher temperature which exists as a condition in the live body. Materials and Methods: Cortical bone specimens from fourteen donors ($63{\pm}21$ years old, 6 females and 8 males) were scanned on a 3T clinical scanner at body and room temperatures to perform T1, $T2^*$, inversion recovery UTE (IR-UTE) $T2^*$ measurements, and two-pool magnetization transfer (MT) modeling. Results: Single-component $T2^*$, $IR-T2^*$, short and long component $T2^*s$ from bi-component analysis, and T1 showed significantly higher values while the noted macromolecular fraction (MMF) from MT modeling showed significantly lower values at body temperature, as compared with room temperature. However, it is noted that the short component fraction (Frac1) showed higher values at body temperature. Conclusion: This study highlights the need for careful consideration of the temperature effects on MRI measurements, before extending a conclusion from ex vivo studies on cortical bone specimens to clinical in vivo studies. It is noted that the increased relaxation times at higher temperature was most likely due to an increased molecular motion. The T1 increase for the studied human bone specimens was noted as being significantly higher than the previously reported values for bovine cortical bone. The prevailing discipline notes that the increased relaxation times of the bound water likely resulted in a lower signal loss during data acquisition, which led to the incidence of a higher Frac1 at body temperature.

소방공무원의 직무질환에 관한 연구 (A Study on Occupational Diseases of Fire Officials)

  • 조광래
    • 시큐리티연구
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    • 제61호
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    • pp.109-135
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    • 2019
  • 본 연구는 소방공무원의 직무질환(진료건수)에 대한 시계열 분석 등 기술적 탐색 연구를 진행하는데 그 목적이 있다. 구체적인 연구결과는 다음과 같다. 첫째, 소방공무원의 직무질환에 대한 평균추이는 ① 내과 질병은 12월이 9.24%로 가장 높고, 2월이 7.76%로 가장 낮고, ② 이비인후과 질병은 12월이 9.29%로 가장 높고, 8월이 6.74%로 가장 낮으며, ③ 피부과 질병은 7월이 10.03%로 가장 높고, 1월과 2월이 7.35%로 가장 낮고, ④ 외과 질병은 11월이 10.38%로 가장 높고, 2월이 5.62%로 가장 낮으며, ⑤ 정형외과 질병은 3월이 9.69%로 가장 높고, 11월이 7.52%로 가장 낮고, ⑥ 신경외과 질병은 4월이 9.33%로 가장 높고, 2월이 6.82%로 가장 낮으며, ⑦ 재활의학과 질병은 12월이 9.47%로 가장 높고, 10월이 7.06%로 가장 낮고, ⑧ 정신건강의학과 질병은 12월이 9.93%로 가장 높고, 5월이 6.51%로 가장 낮은 것으로 나타났다. 둘째, 소방공무원의 직무질환에 대한 계절분해는 ① 내과 질병은 1.075(S) × 189.355(T·C) × 1.174(R) = 238.975(F), ② 이비인후과 질병은 1.023(S) × 69.605(T·C) × 1.040(R) = 74.000(F), ③ 피부과 질병은 1.002(S) × 73.088(T·C) × 0.874(R) = 64.000(F), ④ 외과 질병은 1.099(S) × 27.229(T·C) × 0.669(R) = 20.000(F), ⑤ 정형외과 질병은 1.115(S) × 73.182(T·C) × 1.213(R) = 99.000(F), ⑥ 신경외과 질병은 0.993(S) × 27.836(T·C) × 1.303(R) = 36.000(F), ⑦ 재활의학과 질병은 1.029(S) × 62.417(T·C) × 1.152(R) = 74.000(F), ⑧ 정신건강의학과 질병은 1.210(S) × 8.781(T·C) × 1.035(R) = 11.000(F) 등으로 나타났다.

Quantitative Analysis of Protein-RNA Interaction in A Class I tRNA Synthetase by Saturation Mutagenesis

  • Kim, Sung-Hoon
    • BMB Reports
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    • 제28권4호
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    • pp.363-367
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    • 1995
  • E. coli methionyl-tRNA synthetase is one of the class I tRNA synthetases. The Tryptophane residue at the position 461 located in the C-terminal domain of the enzyme is a key amino acid for the interaction with the anticodon of $tRNA^{Met}$. W461 was replaced with other amino acids to determine the chemical requirement for the interaction with the anticodon of $tRNA^{Met}$. Saturation mutagenesis at the position 461 generated a total of 12 substitution mutants of methionyl-tRNA synthetase. All the mutants showed the same in vivo stability as the wild-type enzyme, suggesting that the amino acid substitutions did not cause severe conformational change of the protein The mutants containing tyrosine, phenylalanine, histidine and cysteine substitutions showed in vivo activity while all the other mutants did not. The comparison of the in vitro aminoacylation activities of these mutants showed that aromatic ring structure, Van der Waals volume and hydrogen bond potential of the amino acid residue at the position 461 are the major determinants for the interaction with the anticodon of $tRNA^{Met}$.

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압전특성 및 부하변화에 따른 압전트랜스포머의 전기적 특성 (Electrical Characteristics of the Piezoelectric Transformer as a Function of Piezoelectric Properties and Load Variations)

  • 민석규;윤광희;류주현
    • 한국전기전자재료학회논문지
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    • 제14권4호
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    • pp.289-296
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    • 2001
  • The piezoelectric transformers of 2.0x10x48 ㎣ size were fabricated with PSN-PMN-PZT(T10 and PNW-PMN-PZT(T2) composition ceramics. Effects of micro structural and piezoelectric properties on the electrical characteristics of the piezoelectric transformers were investigated. Under the fixed output power of 6 W, temperature rise of T1 transformer at the optimum load was smaller than T2 one because of fine grain size effect. Voltage step-up ratio of T1 transformer showed higher value than T2 one T1 transformer showed an excellent properties with voltage step-up ratio of 12.41, efficiency of 95.23% and temperature rise of 7.2$^{\circ}C$ at 200㏀ load resistance. And also, T2 transformer showed an excellent properties with voltage step up ratio of 9.81, efficiency of 95.51% and temperature rise of 9$^{\circ}C$ at 150㏀ load resistance.

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