• 한국미생물·생명공학회지
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• 제11권3호
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• pp.233-239
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• 1983

Bacillus thuringiensis 3ab K- 3 균주를 28$^{\circ}C$에서 UV광으로 돌연변이를 유도한 다음에 42$^{\circ}C$에서 24개의 Temperature-sensitive(ts)돌연변이 균주를 분리하여 42$^{\circ}C$에서의 성장과 항생제 저항성에 대한 성격을 연구하였다. 24개의 ts 돌연변이 균주중에 13개의 ts돌연변이체는 42$^{\circ}C$의 제한온도에서 전혀 성장을 하지 않았으며, 나머지 11개의 돌연변이체는 성장이 28$^{\circ}C$에서 보다 1/2 에서 1/4까지 감축되었다. 이러한 성격에 따라서 ts돌연변이체는 치사군과 비 치사군으로 나눌수 있었다. 또한 B. thuringiensis SI K-2을 nitrosoguanidine으로 28$^{\circ}C$에서 처리하여 7개의 Auxotrophic mutant을 분리하였다. A-N28은 Arg$^{-}$ . Gly$^{-}$ , Leu$^{-}$ , Met$^{-}$ , Ser$^{-}$ , Val$^{-}$ 을 요구했고, A-N 65는 Ala $^{-}$ , Gly$^{-}$ , Leu$^{-}$ , Met$^{-}$ , Ser$^{-}$ , Val$^{-}$ 을 요구했으며 A-N 92는 Gly$^{-}$ , Leu$^{-}$ , Met$^{-}$ 을, A-N115는 7개의 아미노산을 A-N156은 8개를 요구했다. B. thuringiensis 3ab K-3와 SI K-2 는 Penicillin, Ampicillin과 Cephalothin에 저항성을 나타냈고 ts-U171, A-N92와 A-N115는 이 세항생제에 민감성을 나타냈다. Temperature - sensitive돌연변이균주를 42$^{\circ}C$에서 24시간 배양후에 28$^{\circ}C$로 옮기어 배양한 결과 ts-U601, -U603, -U604와 -U171은 성장을 더 이상하지 않았다.

• Journal of Advanced Marine Engineering and Technology
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• 제27권7호
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• pp.921-929
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• 2003

An experimental investigation was performed to study the characteristics of turbulent water flow in a horizontal circular tube by using liquid crystal. To determine some characteristics of the turbulent flow, 2D PIV technique is employed for velocity measurement and liquid crystal is used for heat transfer experiments in water. Temperature visualization was made quantitatively by calibrating the color of the liquid crystal versus temperature using various approaches (TLC technique: Thermochromic Liquid Crystal), and a neural-network algorithm was applied to the color-to-temperature calibration. This study shoud the temperature and time-mean velocity distribution for Re = 2,436, 2,500 and 2,724 along longitudinal sections and the results appear to be physically reasonable.

• Journal of Pharmaceutical Investigation
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• 제38권4호
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• pp.229-234
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• 2008

In the present study, chitosan-glycerophosphate sodium salt solution as a thermosensitive system (TSS) was used to formulate a temperature-sensitive drug delivery system (TSDDS) containing acetaminophen (AAP). The optimized TSS was prepared by measuring gelation temperature, gelation time and rheological properties of TSS. The optimized gelation temperature and time of TSS were $36^{\circ}C$ and 100 seconds, respectively. The viscosity of TSS was also suitable for maintaining gel structure at $37.2^{\circ}C$. The release profiles of TSDDS in PBS/pH 7.4 with various apparatuses and mass loss of TSDDS were investigated. The time required to release 50% of AAP from TSDDS ($t_{50%}$) was 120 min with the formation of pore on the surfaces, which was 2 times longer than that from AAP-chitosan gel. In addition, TSDDS was degraded approximately 80% within 4 hr and then degraded slowly for 20 hrs. In conclusion, AAP-TSS (TSDDS) formulated in this study might be suitable for some specific uses such as subcutaneous injection and rectal formulation.

• Journal of Photoscience
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• 제5권2호
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• pp.53-61
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• 1998

Using a squash plant, a chilling-sensitive species, and a spinach plant, a chilling-resistant one, effects of chilling temperature on the photosynthetic machinery were studied in terms of chlorophyll fluorescence. When thylakoid membranes were isolated and subjected to incubation at different temperatures, spinach showed stable photosystem II activity at the low temperature side, in contrast to squash which showed quite severe inactivation at low temperature. When parameters of chlorophyll fluorescence were examined, chilling in darkness did not affect either Fv/Fm or photochemical and non-photochemical quenching, in both types of plants. However, chilling of squash plants under irradiance of medium intensity caused a specific decrease in Fv/Fm accompanied by a decline in energy-dependent quenching. Contrastingly, photosystem li of spinach plants were not much affected by light-chilling. When the pool size of zeaxanthin was examined after exposure to high light at different temperatures, squash plants was shown to have a much lower content of antheraxanthin + zeaxanthin, as compared to spinach plants, during low-temperature photoinhibition. These results suggest that chilling-sensitive plants have low capacity to dissipate excitation energy nonradiatively, when they are exposed to low-temperature photoinhibition, and, as a consequence, more vulnerable to photoinhibitory, damage to the photosynthetic apparatus.

• 한국대기환경학회지
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• 제24권5호
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• pp.523-537
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• 2008

In Korea, the global warming leads to more frequent high temperature region. increasing the need for research into physical damage caused by high temperature. We therefore analyzed the differences of mortality, caused by extreme heat, among gender and age. We also examined the trend of mortality from high temperature-sensitive diseases. Women are more affected by exposure to high temperature than are men; People over 65 years old have higher mortality rate (1.5 times) than under 65. As for high temperature-related diseases, cerebrovascular disease was the number one cause of death, and chronic lower respiratory disease and cardiovascular disease followed.

• KSBB Journal
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• 제15권6호
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• pp.548-555
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• 2000

온도 및 pH에 동시에 민감한 하이드로젤 poly(N-isopropy­l lacrylamide-co-N,N-dimethylaminopropy Imethacrylamide)을 온도 (13, 15.5, 18, 20.5 및 $23^{\circ}C$)와 pH (10.3, 11.3 및 12.3)를 달리 하여 합성하고 이 젤들의 외형, 기계적 강도, 젤 표면모양, LCST, 수축 pH 및 젤의 팽윤 특성을 연구하였다. 합성온도 및 합성 pH가 낮을수록 젤의 외형은 투명하였 고 기계적 강도는 높았다. SEM 관찰 결과 단백질 보다 더 큰 pore들 때문에 분리효율이 감소되는 것으로 사료된다. 합 성온도나 합성 pH의 증가는 LCST를 낮추었다. 외부온도가 LCST보다 낮은 $25^{\circ}C$ 에 서는 모든 합성온도와 합성 pH에 대 하여 젤은 전 pH에 걸쳐 팽윤된 상태에 있었다. $40^{\circ}C$에서는 LCST보다 높은 온도임에도 불구하고 poly (NIPAAm-co­D DMAPMAAm) 하이드로젤은 pH가 중성 및 산성 영역에서 팽윤되었다. 합성온도가 증가함에 따라 젤 부피가 가장 큰 폭으로 변하는 수축 pH가 더 높아졌다.

• 미생물학회지
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• 제20권4호
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• pp.173-182
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• 1982

From FGSC 159 strain of Aspergillus nidulans, temperature sensitive mutants that are defective in growth and differentiation have been isolated by N-methyl-N'-nitroN-nitrosoguanidine (NTG) treatment. The optimum concentration of NTG and incubation time to get the highest mutation frequency was $100{\mu}g$ per ml and 1 hour, respectively. The survival frequency was 1%. Among the isolated mutants, five strains that were affected in early steps of differentiation were selected for further studies and named smK, smY, smB, smF, and smZ. The execution point of each mutant was determined and the growing pattern of each mutant at the restrictive temperature was observed under the microscope. Growth of mutant was arrested near at the execution point. From genetic analysis, each temperature-sensitive mutants was thought to have a single recessive gene. The genes of smK, smY, smB, smF, and smZ are linked to the chromosome VII, IV, VIII, I, and VI, respectively. It can be concluded that the genes controlling the differentiation are widely dispersed in the genome. From the results of mutant, smK, it is considered that a single gene can affect a function (functions) which act(s) at two different steps during differentiation.

• Macromolecular Research
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• 제16권7호
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• pp.637-643
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• 2008

A combination of magnetic and temperature-responsive properties in the same polymer composites is expected to increase their potential applications in the biomedical field. Accordingly, micron-sized magnetite/polystyrene/poly(2-dimethylaminoethyl methacrylate-ethyleneglycol dimethacrylate), which are abbreviated as $Fe_3O_4$/PS/P (DM-EGDM) composite polymer particles, were prepared by the seeded copolymerization of DM and EGDM in the presence of magnetite/polystyrene ($Fe_3O_4$/PS) particles. $Fe_3O_4$/PS/P(DM-EGDM) composite particles with magnetic properties showed a temperature-sensitive phase transition at approximately $31^{\circ}C$. The adsorption behavior of the low molecular weight emulsifiers and trypsin (TR) as biomolecules were examined on $Fe_3O_4$/PS/P(DM-EGDM) composite polymer particles at different temperatures. The native conformation of TR was followed by measuring the specific activity under various adsorption conditions. The activity of the adsorbed TR on composite polymer particles was higher than those of the tree TR and TR adsorbed on $Fe_3O_4$/PS particles.

• 한국안전학회지
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• 제11권1호
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• pp.53-59
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• 1996

To protect the damages or the disasters caused by overheating of industrial electric equipments or electric home appliances, a temperature sensitive thermal fuse is generally used in those equipments. Thermal fuses cutoff the current flow when the temperature of the electric equipments are abnormally overheated and over the certain temperature. Therefore thermal fuse is one of the most important elements in the sense of safety. Thermal fuses are classified into two types according to thermally sensitive materials, a low temperature melting alloy and an organic chemical compound. Domestic products of thermal fuses are now only with an organic chemical compound. Domestic products tested by using cutoff test and aging test etc. are satisfied UL specification. It's shown that the accuracy and the precision of the domestic products are as good as those of the overseas products obtained UL mark. However, some of domestic products show the reclosing problem which is mainly related the safety. This problem should be solved to make the reliable thermal fuses. In this paper, our Interest is to find out the causes of reclosing. In the comparison between thermally sensitive materials occurred reclosing and those occurred no reclosing, the test effects show that the characteristics of emitting heat and absorbing heat are different.

• Structural Monitoring and Maintenance
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• 제8권4호
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• pp.379-402
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• 2021

Traditional approaches for structural health monitoring (SHM) seldom take ambient uncertainty (temperature, humidity, ambient vibration) into consideration, while their impacts on structural responses are substantial, leading to a possibility of raising false alarms. A few predictors model-based approaches deal with these uncertainties through complex numerical models running online, rendering the SHM approach to be compute-intensive, slow, and sometimes not practical. Also, with model-based approaches, the imperative need for a precise understanding of the structure often poses a problem for not so well understood complex systems. The present study employs a data-based approach coupled with Empirical mode decomposition (EMD) to correlate recorded response time histories under varying temperature conditions to corresponding damage scenarios. EMD decomposes the response signal into a finite set of intrinsic mode functions (IMFs). A two-dimensional Convolutional Neural Network (2DCNN) is further trained to associate these IMFs to the respective damage cases. The use of IMFs in place of raw signals helps to reduce the impact of sensor noise while preserving the essential spatio-temporal information less-sensitive to thermal effects and thereby stands as a better damage-sensitive feature than the raw signal itself. The proposed algorithm is numerically tested on a single span bridge under varying temperature conditions for different damage severities. The dynamic strain is recorded as the response since they are frame-invariant and cheaper to install. The proposed algorithm has been observed to be damage sensitive as well as sufficiently robust against measurement noise.