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The objective of this study was to analyze mycotoxin contents in Korean barley and wheat infected with Fusarium sp. The major contaminant was determine among deoxynivalenol, nivalenol (NIV), and zearalenone, as well as diminution rate of mycotoxin contents by milling, washing, and boiling processes. NIV was found as a major mycotoxin contaminant in Korean barley and wheat, and bran showed higher contamination level than the inner part in whole infected cereal. The results indicate that the milling process of the diseased barley and wheat showed dramatic diminution rate of 84.4%. Furthermore, the washing on barley reduced mycotoxin infection up to 81.0%, and boiling showed 82.7% diminution effect.

Municipal sewage treatment plants (STPs) are thought to be important point sources of microplastics in freshwater systems and many peer-reviewed articles have been published on this issue since mid-2010s. In this review, we summarize existing literature on the occurrence of microplastics in STPs and experimental methods used for isolation and identification of microplastics. The number concentrations of microplastics in STP influents were 15.1-640 L-1 , whereas those in the STP effluents were highly variable and ranged from not detectable to 65 L-1 . For most of cases, conventional STPs are removing microplastics very effectively. Fragments and fibers are dominant shapes of microplastics. Thermoplastics (polyethylene and polypropylene) and polyester are the predominant materials recovered. Although further research is needed, size distribution of microplastics in STPs is likely to follow a power law, implying that different studies using different size cutoffs may be compared after establishing a power law relationship.

Concentration of antibiotics including a tetracycline group (TCs) of tetracycline (TC), chlortetracycline (CTC), and oxytetracycline (OTC), a sulfonamide group (SAs) of sulfamethoxazole (SMX), sulfathiazole (STZ), and sulfamethazine (SMT), an ionophore group (IPs) of lasalocid (LSL), monensin (MNS), and salinomycin (SLM), and a macrolide group (MLs) of tylosin (TYL) was determined from samples collected from the agricultural soil, stream water, and sediment. For the agricultural soil samples, the concentration of TCs had the highest value among all tested antibiotic's groups due to its high accumulation rate on the surface soils. The lower concentrations of SAs in the agricultural soils may be resulted from its lower usage and lower distribution coefficient (Kd) compared to TCs. The concentration of TCs in stream water was significantly increased through June to September. It would be likely due to soil loss during an intensive rainfall event and a reduction of water level after the monsoon season. A significant amount of TCs in the sediment was also detected due to its accumulation from runoff, which occurred by complexation of divalent cations, ion exchange, and hydrogen bonding among humic acid molecules. To ensure environmental or human safety, continuous monitoring of antibiotics residues in surrounding ecosystems and systematic approach to the occurrence mechanism of antibiotic resistant bacteria are required.

In recent years, many agricultural scientists are studying on eco-friendly farming methods. Among of lots of the methods, the natural insecticides are highly motivated and interested due to their safety and biodegradable issues, and readily available source of bioinsecticides. In this study, the crude extract of custard apple (Annona reticulata L.) seed and its three fractions which were separated based on polarity indexes were examined for their insecticidal activities against Myzus persicae Sulzer and Nilaparvata lugens S.. The crude extract (Aceton/MeOH) showed strong insecticidal activities against both insects at 3.00 mg/mL (

The thermal treatment for carbon nanotube was applied to remove the water, metal catalyst and other impurities in carbon nanotube. The surface of carbon nanotube was changed into open structure with acid treatment by mixed solution of and . The dispersion property of the functionalized and modified carbon nanotube was assessed with naked eyes by dispersing it in DMF. Carbon nanotube mixd polyurethane film was made to estimate the dispersion property by reflectance of the film with UV-Vis spectrometer. Also the internal structure of carbon nanotube was observed with SEM and TEM and thermal pyrolysis property of the carbon nanotube was measured by TGA and DSC. The surface modification of carbon nanotube by thermal and acid treatments improved the dispersion property of carbon nanotube/polyurethane mixed materials.

The objectives of this paper are to measure the heat transfer and pressure drop of the plate heat exchangers for absorption system applications. Three types of plate heat exchangers with different chevron angles are tested in the present experiment. Heat transfer and pressure drop performance of plate heat exchangers are measured in various operating conditions, and compared each other. The results show that the heat transfer rate of high theta (120°) and mixed theta plate heat exchanger increases about 118% and 98% at the solution flow rate 350 kg/h compared to that of low theta (60°), respectively. The effectiveness of high theta was evaluated about 0.53 ~ 0.85 in this experimental range. The experimental correlations of the Nu and f were developed with error bands of ±7% and ±12%.

To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides (fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008~7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001~0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01~7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07~ 3.06 % from Kongju agricultural land to watershed after applied pesticides.

The objectives of this paper are to study the characteristics of heat transfer and pressure drop of the micro channel heat exchangers using diffusion bonding technology. Four types of heat exchangers are designed and manufactured, which are straight type, long dot type, splited wavy type and straight double side type. Heat transfer and pressure drop performance of each heat exchangers are measured in various operating conditions, and compared each other. The results show that the (j/f) 1/3 performance of splited wavy type and long dot type increases about 10.3% and 6.1% at the Reynolds number 470 compared to that of straight type, respectively. On the other hand, (j/f) 1/3 performance of straight double side type decreases 19.7%.기호설명A s : 열전달면적 [mm 2 ] C: 열용량 [W/℃]C p : 비열 [J/kg․℃]D h : 수력직경 [mm] ff: 인자 j j: 인자 : 질량유량 [kg/h]Nu : 누셀트수△ P: 압력강하 [kPa] Q: 열전달률 [kW]Re : 레이놀즈수 T: 온도 [℃]Δ T: 온도차 [℃] U: 총괄열전달계수 [kW/m 2 ․℃]e : 유용도 †책임저자, 회원, 한국생산기술연구원 에너지설비기술지원센터 E-mail : kwonok@kitech.re.kr TEL : (041)589-8528 FAX : (041)589-8330 * 회원, 한국생산기술연구원 에너지설비기술지원센터

The object of this paper is to study on the thermal performance of a micro channel water block for computer CPU cooling. The effects of liquid flow rate, micro channel width and height on the thermal performances of water block are investigated experimentally. The water block was fabricated Al and machined with a micro milling. The water block consisted of rectangular micro channels 0.5 to 0.9 mm width and 1.5 to 4.5 mm height. The experiments were conducted using deionized water, over a liquid flow rate ranging from 0.2 to 2.0 kg/min. The base temperature and thermal resistance decrease with increasing of liquid flow rate. The increase of a channel height is more effective on the thermal resistance than the decrease of a channel width. At the flow rate of 0.7 kg/min, input power of 100 W, the base temperature and thermal resistance of sample 6 is 33℃ and 0.13 ℃/W respectively. 기호설명 C p : 비열 [J/kg․℃] D h : 수력직경 [mm] H ch : 채널높이 [mm] I : 전류 [A]△ P : 압력강하 [kPa] Q : 열전달량 [W]

The optimum extraction conditions of green tea used for a bath were investigated for application to textiles. The stability of the extracts and content of active ingredients were analyzed as well. The extraction was more effective in water and methanol than in ethanol. The optimum extraction temperature was determined as in water and in methanol. The solid extracts were obtained about 7% in water and 9% in methanol on the weight of dry green tea. The extracts were more stable in acid and neutral conditions than in alkaline region. From the analysis of contents of active ingredients, about 20% of effective catechins was appeared to be contained in the extract solid, which was thought to be available for application to textiles.

The rapid thermal response(RTR) molding is a novel process developed to raise the temperature of mold surface rapidly in the injection stage and then cool rapidly to the ejection temperature by air or water. The objectives of this paper are to investigate the effect of mold temperature, pressure and thickness of micro pattern molding and to provide a optimization of RTR injection molding for micro pattern from Moldflow simulation. Optimal minimum temperature and pressure was found without shortcut according to thickness. Filling percentage was influenced by glass transition temperature with the kinds of resin. Optimal temperature is slightly higher than glass transition temperature irrespectively of pressure, thickness, the kinds of resin in the micro pattern molding.

Rapid mold heating has been recent issue to enable the injection molding of thin-walled parts or micro/nano structures. Induction heating is an efficient way to heat a conductive workpiece by means of high-frequency electric current caused by electromagnetic induction. Because the induction heating is a convenient and efficient way of indirect heating, it has various applications such as heat treatment, brazing, welding, melting, and mold heating. The present study covers an experimental investigation on the rapid heating using the induction heating and rapid cooling using a vortex tube in order to eliminate an excessive cycle time increase. Experiments are performed in the case of a steel cup mold core with various heating and cooling conditions. Temperature is measured during heating and cooling time, from which appropriate mold heating and cooling conditions can be obtained.

This paper presents experimental results of heat and mass transfer investigation of the falling film absorber (with strong lithium bromide solution) for a small household absorption chiller/heater. Various components (e.g. low temperature generator, absorber and evaporator) were arranged concentrically in cylindrical form such that the helical-arrangement of the heat exchangers allowed the system to be more compact than the conventional system. Measurements from the helical absorber were compared with data from the literature. The comparison revealed that the heat and mass transfer performance of the helical absorber tube is similar to the existing tube bundle absorber. As a result, the proposed helical absorber shows a good potential due its reduced size and weight for the future designs of small capacity absorption chillers/heaters.

An experimental study has been performed to investigate the heat and mass transfer performance in a falling film absorber of a small-sized absorption chiller/heater. The components of the chiller/heater were concentrically arranged in a cylindrical form with a low temperature generator, an absorber and an evaporator from the center. The arrangement of such a helical-type heat exchanger makes the system more compact compared to a conventional one. As a working fluid, LiBr + LiI + LiNO 3 + LiCl solution is used to get improved heat transfer effect. The heat and mass transfer coefficients of the helical absorber provide similar values compared with the data obtained for horizontal absorbers at similar solution flow rates. The heat and mass transfer coefficients of LiBr + LiI + LiNO 3 + LiCl solution increase as the solution flow rate per unit length increases. However, if the solution flow rate is larger than 0.03 kg/m s, the heat and mass transfer increase is minimal. Thus, 0.03 kg/m s is recommended as an optimal solution flow rate. The heat and mass flux performance of LiBr + LiI + LiNO 3 + LiCl solution shows the tendency of 2–5% increase compared with that of LiBr solution.

In this study, heat and mass transfer characteristics of five components solution (LiBr＋Lil＋LiNO＋LiCl＋) which could be substituted for commonly used LiBr solution are tested using a helical absorber. The arrangement of helical-typed heat exchangers allows to make the system more compact as compared to conventional one. The effects of experimental parameters, such as the solution flow rate, cooling water, solution temperature, solution concentration and surfactant have been investigated in view of the heat and mass transfer. The results of the experiment of heat and mass transfer performance show that five components solution should have 2％ higher concentration fur equal absorption capacity of LiBr solution. But considering that five components solution have higher solubility than LiBr solution about 4％ high concentration, five components solution could be applied to a small sized water cooled or air cooled absorption chiller/heater. The increase of heat and mass transfer coefficient by surfactant addition is about 25∼30％ and 23∼40％ respectively.

This study was concerned with the enhancement of mass transfer by surfactant added to the aqueous solution of LiBr. Different vertical inner tubes were tested with and without an additive of normal octyl alcohol. The test tubes were a bare tube, groove tube, corrugate tube and inserted spring tubes. The additive concentration of normal octyl alcohol as a surfactant is about 0.08mass%. The Sherwood number was measured as a function of film Reynolds number 20~200. The experimental results were compared with those which use no surfactant. The enhancement of mass transfer by Marangoni convection effect which was generated by addition of the surfactant is proved for each testing tube Especially, it is clarified that the tube with the spring has the highest enhancement effect. A correlation of the experimental mass transfer data for the bare, groove, corrugate and insert spring tubes results expressed as the form of Sh

A large amount of consumed energy is released to the environment as waste heat, which may be used directly in some applications for useful purposes. Thus, from the standpoint of energy conservation, it will be meaningful to investigate systems with waste heat utilization. It has long been indicated that absorption cycles may have good potential applications for enhancing energy conservation via waste heat recovery. As such they have often been identified as an appropriate subject for research and development. Along this line, this paper also examines the development of an absorption cycle with waste heat utilization. More specifically, this study investigates a double-effect LiBr–water absorption cycle which uses exhaust gases from the burner of the high-temperature generator to preheat the weak absorbent solution on its way from the absorber to the low-temperature generator. The overall performance of the absorption heater/chiller system is analyzed and discussed on the basis of experimental results.

The steam burn caused by an electric rice-cooker is a unique mode of burn injury in Asian countries, especially Korea and Japan. This type of burn injury is characterized by 1) occurring most frequently on the volar aspect of the hand in toddlers younger than 2 years of age (92.8%); 2) the depth of burns are normally deep second-degree to third-degree (98%) and usually need surgery at the time of injury; 3) flexion contractures of multiple finger joints and web space contracture are common sequelae. We hypothesized that primary full-thickness skin graft (FTSG) would give more reliable results and eliminate the late reconstructive procedures. Between January 1997 and September 1999, 36 patients underwent primary FTSG, and the results of this primary FTSG group were compared with 124 patients who were treated with split-thickness skin graft (STSG; 79/124; 63.7%) or by conservative management (45/124; 36.3%), and readmitted for the correction of hand deformities between September 1995 and September 1999. In the primary FTSG group, 11.1% (4/36) of mild web contractures and 5.5% (2/36) of finger joint contractures were documented, and these did not require the reconstructive procedure during a follow-up period of 8.8 +/- 4.8 months. In 124 patients of the primary STSG or conservative group, the mean time interval to reoperation was 8.9 +/- 4.0 months and all patients received FTSG for correction of late hand deformities. In a retrospective study of the primary STSG group, 42 of 53 patients (79.2%) received reconstructive procedure during a 5-year follow-up period. In this report, we introduce the nature of steam burn caused by electric rice-cooker and propose that primary FTSG may be a reliable method for the treatment of this more severe type of acute burn in pediatric patients.

Ice formation in a horizontal circular has been studied numerically. From the numerical analysis results, it was found that there were three types of freezing patterns and that the freezing phenomenon was affected largely by density inversion and cooling rate. The type of freezing pattern largely depends on the secondary flow, which is generated by density inversion. When supercooling energy is released before the development of the secondary flow, an annular ice layer grows. If the energy is released when the secondary flow is considerably developed and the supercooled region is removed to the upper half part of the cylinder, an asymmetric ice layer grows. If the energy is released after perfect development of the secondary flow, instantaneous dendritic ice formation over the full region occurs. Furthermore, the secondary flow was found to have an effect on heat transfer characteristics. The heat transfer rate becomes small at the instant when the secondary flow is generated, but it hecomes large with the development of the secondary flow. It is concluded that for the facilitation of heat transfer it is desirable to keep water, in its liquid phase until the secondary flow is perfectly developed. This study gives an instruction on the performance improvement of a capsule-type ice storage tank.

A cycle analysis was achieved to predict the characteristics by comprehensive modelling and simulation of an air-cooled, double-effect absorption system using the new H 2 O/LiBr+HO(CH 2 ) 3 OH solution. The simulation results showed that the new working fluid may provide the crystallisation limit 8% higher than the conventional H 2 O/LiBr solution. With a crystallisation margin of 3 wt%, the optimal solution distribution ratio was found to be in the range of 37–39%. Variation of cooling air inlet temperature had a sensitive effect on the cooling coefficient of performance (COP) and corrosion problem. The simulation of heat exchangers with UA value revealed that the absorber and evaporator were relatively important for an air-cooled system compared with the condenser and the low temperature generator. The effects of cooling air flow rate, circulation weak solution flow rate and chilled water inlet temperature were also examined. The new working fluid may provide a COP approximately 3% higher than the conventional H 2 O/LiBr solution in normal conditions of circulation weak solution.

In this paper, an experimental study of the absorption process of water vapor into lithium bromide solution is reported. For the purpose of developing high performance absorption chiller/heater utilizing lithium bromide solutions as working fluid, it brings the largest contribution to improve the performance of the absorber which normally requires the largest surface area among the four heat exchangers of the system. The performance of four types of absorber tubes; bare tube, bumping bare tube, floral tube and twisted floral tube, have been experimentally evaluated. The results show that the floral tube and the twisted floral tube show about 40% higher heat and mass transfer performance than the bare tube which is conventionally used in absorbers.

This study investigates the effect of additives such as normal octyl alcohol into lithium bromide-water (LiBr/H2O) solutions in the absorption and generation processes of absorption refrigerating machines. The experimental results confirmed the positive effect of additive use in the absorber. Little is known, however, on the effect of additives on generator performance. In this study, the authors carried out experiments to investigate the possible positive or negative effects of additive, which enhances the absorption process, on the generator behavior. The results showed heat transfer at the generator improved as pressure increased and concentration decreased; the boiling heat transfer coefficient was shown to be more strongly influenced by concentration than by pressure. The boiling curves showed that the heat transfer of solution in the generator was not significantly affected by the addition of surfactant. The result of this study showed that the surfactant in absorption heater/chiller made enhanced absorption effect in the absorber but it didn't give any influence in the generator. Therefore the additive was devoted to helping high performance in the absorption system.

This study was designed to find the effects of two kinds of dust-free garments with (A) and without (B) frozen gel strip (FGS), and half-naked clothing (brassiere and shorts; C) on thermophysiological parameters and on temperature and humidity within clothing. The heart rate, rectal, and skin temperatures as well as sweat rate and clothing microclimate were measured during 140 min in 9 healthy females. Inquiries were also made into the subjective rating of thermal, humidity, and comfort sensations. The main findings in our experiments are as follows: (a) Physiological parameters such as rectal and skin temperatures (chest and forehead), heart rate, and sweat rate were clearly lowest in garb C, intermediate in garb A, and highest in garb B throughout the experiment; (b) Temperature and humidity within clothing were lower in garb A than in garb B; (c) More than half of the 9 participants decreased thermal sensation by wearing garb A. These results suggest that the usage of FGS could improve the heat load in lightly working participants wearing dust-free garments.

4062 Background: It is well known that lymphocytic infiltration around tumor can be considered as a host immune reaction against tumor cells, although prognostic implication of lymphocyte infiltrat...

Grid and Web service technology can be used as a solution for the resource shortage problem. These two technologies are used to be applied to MPI (message passing interface) applications to design a framework to deploy MPI applications on OGSA (open Grid service architecture). In particular, we modeled MPI applications as WS-Resources. We call the WS-Resource “MPI resource” and it is composed of an MPI application and its associated dynamically created running environment. Thus, an MPI resource represents one MPI task. Through this model, MPI applications can be published to the world of the Grid. In addition, running environment is dynamically created from resources chosen among distributed idle resources on the Grid. Deployed MPI resources are utilized by other services. Especially in virtual organizations, MPI resources can have the roles responsible for computing task as computing resources for compute-intensive works and data resources for data-intensive works.

An experimental study has been performed to investigate the heat and mass transfer performance in a falling film absorber of a domestic small-sized absorption chiller/heater. The components of the chiller/heater were concentrically arranged in a cylindrical form with low temperature generator, an absorber and an evaporator from the center. The arrangement of such a helical-type heat exchanger allows to make the system more compact as compared to a conventional one. As a working fluid, the LiBr+LiI+LiNO3+LiCl solution is used to get improved heat transfer. The heat and mass flux performance of the LiBr+LiI+LiNO3+LiCl solution shows 2 ∼ 5% increase than that of the LiBr solution. When a surfactant in the LiBr+LiI+LiNO3+LiCl solution is used, the performance of heat and mass transfer improves 15 ∼ 20%. This result shows the LiBr+LiI+LiNO3+LiCl solution with a surfactant can be applied to a small-sized absorption chiller/heater.

Proximal muscle weakness can be induced by many diseases, such as muscular dystrophies, inflammatory muscle diseases, and polymyalgia rheumatica. Differential diagnosis of these diseases is important. The patient had proximal muscle weakness with a normal creatine kinase (CK) level. Our initial diagnosis was polymyalgia rheumatica because the CK level was normal. The patient was treated with low-dose corticosteroid. However, the muscle weakness did not improve. The diagnosis of polymyositis was confirmed by a muscle biopsy. We suggest that if the patient has typical symptoms with normal CK, then evaluations for inflammatory muscle diseases are essential. (Korean J Med 2014;86:258-262)

In this study, empirical and numerical analyses on the screening current-induced field (SCIF) characteristics of a non-insulated (NI) GdBCO-coated conductor single-pancake coil were conducted. Charge and discharge tests were carried out to induce an SCIF in the NI test coil. The SCIF in the NI coil was identified by comparison between the measured and calculated magnetic fields. The experimental results exhibit an increase of the SCIF with increasing an operating current, as well as a logarithmic decay of the SCIF as a function of time. Moreover, the SCIF was not affected by the slow discharge of the NI coil. The estimation of the SCIF based on the critical-state model in a thin film using the finite element method was in fairly good agreement with the experimental results.

The thermal and electrical characteristics of two GdBCO-coated conductor racetrack coils, one insulated with Kapton insulation and the other without turn-to-turn insulation, were investigated by typical voltage–current measurement, charge–discharge, sudden discharge, and over-current tests with respect to external pressures applied to the straight sections of the coils. The test results show that the thermal and electrical stabilities of the racetrack coil without insulation were enhanced considerably with increasing external pressure up to 0.5 MPa, whereas those of the insulated coil were not affected by the pressure. The non-insulated HTS racetrack-type coil with improved turn-to-turn thermal contact in the straight sections may have the potential to be manufactured into field coils for HTS wind turbine generators with highly enhanced thermal and electrical stabilities.

GdBCO single-pancake coils wound with Kapton insulation every 3, 6, 9 turns, and without insulation, were characterized by charge–discharge and over-current tests. The magnetic field saturation at higher currents than the critical current was affected by the portion of the insulated turns that restricted the surplus current flow away from the azimuthal current path. The charge–discharge delay decreased with the increase of the portion of the insulated turns, which suggested that partial insulation winding may be effective for use in HTS power applications. Magnetic field loss of the coils with reduced insulation at excessive high currents was mainly affected by the decrease in ampere-turns due to the electrically shorted-circuits between the non-insulated turns, which resulted in the over-current flow bypass through the turn-to-turn contacts.

Purpose: The aim of this study was to evaluate chronological change of quality of life after surgery in patients with gastric cancer during one year postoperatively. Materials and Methods: Quality of life data were obtained from 272 gastric cancer patients who underwent curative gastrectomy between September 2008 and February 2011 at the Kyungpook National University Hospital. The Korean versions of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core (QLQ) 30 with gastric cancer-specific module, the EORTC QLQ-STO22 were used to assess quality of life. All patients had no evidence of recurrence or metastasis during the first postoperative year. Patients were asked to complete the questionnaire, by themselves preoperatively, 3-, 6-, 9-, and 12-months postoperatively. Results: Physical functioning score and role functioning score significantly decreased at first 3 months after surgery and the significant differences were noticed until 12 months after surgery. Emotional functioning score started with the lowest score before surgery and significant improvement was shown 6 months after surgery. Most symptom scores and STO-22 scores were highest at 3 months after surgery and gradually decreased, thereafter. Eating restriction, anxiety, taste, body image scores was highest at 3 months after surgery without significant decrease afterwards. Conclusions: Most scales worsened after surgery and gradually recovered afterwards with some differences in rate of recovery. However the scales did not fully recover by 1 year period. Further follow-up after 1 year would be helpful in determining which scales are permanently damaged and which are just taking longer time to recover.

Isosulfan blue dye can be used to mark the sentinel lymph node during various surgeries. The dye was known to have minimal side effects, but recently a few cases of an anaphylactic reaction were reported in melanoma and breast surgery. We experienced an anaphylactic reaction during peritumoral injection of this dye in a patient with cervical cancer. Immediately after dye injection, the patient showed an anaphylactic reaction with cardiovascular collapse and oxygen desaturation. We resuscitated the patient and she recovered without complications.

Endotracheal tube obstruction causes serious complications, including cardiovascular instability, pneumothorax, pulmonary edema and brain death. A 64 year old man was scheduled for a laminectomy and instrument fixation due to spinal stenosis. The patient was intubated with a 8.5 mm reinforced endotracheal tube and turned to the prone position. An hour later, signs of partial endotracheal obstruction were observed including high airway pressure and low tidal volume. Airway obstruction signs were aggravated as the operation proceeded. Two hour later, passage of a suction catheter was difficult and PaCO2 increased significantly, so we temporarily stopped the operation and turned the patient to supine. After that, we exchanged the tube with another tube and found the distal tip of the reinforced tube impacted with mucous secretions.