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We aimed to investigate the effect of chronic particulate matter (PM) exposure on bleomycin-induced lung fibrosis in a rat model using chest CT, histopathologic evaluation, and RNA-sequencing. A bleomycin solution was intratracheally administrated to 20 male rats. For chronic PM exposure, after four weeks of bleomycin treatment to induce lung fibrosis, PM suspension (experimental group) or normal saline (control group) was intratracheally administrated for 10 weeks. Chest CT was carried out in all rats, and then both lungs were extracted for histopathologic evaluation. One lobe from three rats in each group underwent RNA sequencing, and one lobe from five rats in each group was evaluated by western blotting. Inflammation and fibrosis scores in both chest CT and pathologic analysis were significantly more aggravated in rats with chronic PM exposure than in the control group. Several genes associated with inflammation and immunity were also upregulated with chronic PM exposure. Our study revealed that chronic PM exposure in a bleomycin-induced lung fibrosis rat model aggravated pulmonary fibrosis and inflammation, proven by chest CT, pathologic analysis, and RNA sequencing.

Background Lung injury elicited by respiratory exposure to humidifier disinfectants (HDs) is known as HD-associated lung injury (HDLI). Current elucidation of the molecular mechanisms related to HDLI is mostly restricted to fibrotic and inflammatory lung diseases. In our previous report, we found that lung tumors were caused by intratracheal instillation of polyhexamethylene guanidine phosphate (PHMG-p) in a rat model. However, the lung cancer-related genetic changes concomitant with the development of these lung tumors have not yet been fully defined. We aimed to discover the effect of long-term exposure of PHMG-p on normal human lung alveolar cells. Methods We investigated whether PHMG-p could increase distorted homeostasis of oncogenes and tumor-suppressor genes, with long-term and low-dose treatment, in human pulmonary alveolar epithelial cells (HPAEpiCs). Total RNA sequencing was performed with cells continuously treated with PHMG-p and harvested after 35 days. Results After PHMG-p treatment, genes with transcriptional expression changes of more than 2.0-fold or less than 0.5-fold were identified. Within 10 days of exposure, 2 protein-coding and 5 non-coding genes were selected, whereas in the group treated for 27–35 days, 24 protein-coding and 5 non-coding genes were identified. Furthermore, in the long-term treatment group, 11 of the 15 upregulated genes and 9 of the 14 downregulated genes were reported as oncogenes and tumor suppressor genes in lung cancer, respectively. We also found that 10 genes of the selected 24 protein-coding genes were clinically significant in lung adenocarcinoma patients. Conclusions Our findings demonstrate that long-term exposure of human pulmonary normal alveolar cells to low-dose PHMG-p caused genetic changes, mainly in lung cancer-associated genes, in a time-dependent manner.

There have been no studies on the effects of polyhexamethylene guanidine phosphate (PHMG) after a long period of exposure in the rodent model. We aimed to evaluate long-term lung damage after PHMG exposure using conventional chest computed tomography (CT) and histopathologic analysis in a rat model. A PHMG solution was intratracheally administrated to 24 male rats. At 8, 26, and 52 weeks after PHMG instillation, conventional chest CT was performed in all rats and both lungs were extracted for histopathologic evaluation. At 52 weeks after PHMG instillation, four carcinomas had developed in three of the eight rats (37.5%). Bronchiolo-alveolar hyperplasia and adenoma were found in rats at 8, 26, and 52 weeks post-instillation. The number of bronchiolo-alveolar hyperplasia significantly increased over time (P-value for trend< 0.001). The severity of lung fibrosis and fibrosis scores significantly increased over time (P-values for trend = 0.002 and 0.023, respectively). Conventional chest CT analysis showed that bronchiectasis and linear density scores suggestive of fibrosis significantly increased over time (P-value for trend < 0.001). Our study revealed that one instillation of PHMG in a rat model resulted in lung carcinomas and progressive and irreversible fibrosis one year later based on conventional chest CT and histopathologic analysis. PHMG may be a lung carcinogen in the rat model.

The inhalation of humidifier disinfectants (HDs) is linked to HD-associated lung injury (HDLI). Polyhexamethylene guanidine (PHMG) is significantly involved in HDLI, but the correlation between chloromethylisothiazolinone (CMIT) and HDLI remains ambiguous. Additionally, the differences in the molecular responses to PHMG and CMIT are poorly understood. In this study, RNA sequencing (RNA-seq) data showed that the expression levels of metallothionein-1 (MT1) isoforms, including MT1B, MT1E, MT1F, MT1G, MT1H, MT1M, and MT1X, were increased in human pulmonary alveolar epithelial cells (HPAEpiCs) that were treated with PHMG but not in those treated with CMIT. Moreover, upregulation of MT1B, MT1F, MT1G, and MT1H was observed only in PHMG-treated HPAEpiCs. The protein expression level of metal regulatory transcription factor 1 (MTF1), which binds to the promoters of MT1 isoforms, was increased in PHMG-treated HPAEpiCs but not in CMIT-treated HPAEpiCs. However, the expression of early growth response 1 (EGR1) and nuclear receptor superfamily 3, group C, member 1 (NR3C1), other transcriptional regulators involved in MT1 isomers, were increased regardless of treatment with PHMG or CMIT. These results suggest that MTF1 is an essential transcription factor for the induction of MT1B, MT1F, MT1G, and MT1H by PHMG but not by CMIT.

Colorectal cancer (CRC) is the second‐leading cause of cancer‐related mortality worldwide, which may be effectively reduced by early screening. Colon cancer secreted protein‐2 (CCSP‐2) is a promising blood marker for CRC. An electric‐field effect colorectal sensor (E‐FECS), an ion‐sensitive field‐effect transistor under dual gate operation with nanostructure is developed, to quantify CCSP‐2 directly from patient blood samples. The sensing performance of the E‐FECS is verified in 7 controls and 7 CRC samples, and it is clinically validated on 30 controls, 30 advanced adenomas, and 81 CRC cases. The concentration of CCSP‐2 is significantly higher in plasma samples from CRC and advanced adenoma compared with controls (both P < 0.001). Sensitivity and specificity for CRC versus controls are 44.4% and 86.7%, respectively (AUC of 0.67), and 43.3% and 86.7%, respectively, for advanced adenomas (AUC of 0.67). CCSP‐2 detects a greater number of CRC cases than carcinoembryonic antigen does (45.6% vs 24.1%), and the combination of the two markers detects an even greater number of cases (53.2%). The E‐FECS system successfully detects CCSP‐2 in a wide range of samples including early stage cancers and advanced adenoma. CCSP‐2 has potential for use as a blood‐based biomarker for CRC.

In article number 1802115, Kwan Hyi Lee, Seung‐Jae Myung, and co‐workers successfully develop an electric field effect colorectal sensor (E‐FECS) equipped with a thin film transistor‐chipset, a disposable multiwell gate, and an integrated measurement box to detect colon cancer secreted protein‐2 (CCSP‐2) in blood samples from human colorectal cancer (CRC) patients. The E‐FECS system has the potential as a diagnostic tool for postoperative monitoring and early detection of CRC.

Republic of Korea has established its performance-based navigation (PBN) implementation plan in 2010 for ensuring a smooth transition to PBN operations and relevant new flight procedures are being developed in accordance with the roadmap. Various Navigation aids (NAVAIDs) like global navigation satellite systems (GNSS), distance measuring equipment (DME), VHF omnidirectional range (VOR), inertial navigation system (INS) are used to support PBN procedures. Among them, GNSS would play a central role in PBN implementation. However, vulnerability of satellite navigation signals to artificial and natural interferences has been discovered and various alternative positioning, navigation and timing (APNT) technologies are under development in many countries. In this paper, we study whether continuous PBN operations can be achievable without GNSS signals. As a result, it shows that some of the domestic airports require the construction of APNT in the approach area.

Multilateration(MLAT) is commonly used in civil and military surveillance applications to accurately locate an aircraft, vehicle or stationary emitter. MLAT calculates the TDOA of signals by transmitted aircraft and determines the aircraft’s location. With more than four receivers it is possible to estimate the 3D position of the aircraft by calculating the intersection of the resulting hyperbolas and the system integrity. In this study, our objectives are to apply MLAT technique to Jeju terminal control area and to propose a MLAT receiver network to properly estimate the positions of aircraft approaching this area. Based on computer simulations, we determine locations of ground receivers in Jeju terminal control area, calculate estimated position errors of the aircraft with respect to the selected receiver networks, and find the best receiver network with the least position error.

A versatile biomarker for detecting colonic adenoma and colon cancer has yet to be developed. Colon cancer secreted protein-2 (CCSP-2) is a protein specifically expressed and secreted in colon adenomas and cancers. We developed a fluorescent imaging method based on CCSP-2 targeting for a more sensitive and specific detection of colorectal tumors. CCSP-2 expression was evaluated in human colon adenoma and colorectal specimens. Anti–CCSP-2 antibody was labeled with a near-infrared fluorescent dye, FPR-675, and molecular imaging of surgical human colorectal tumors was performed. Immunohistochemistry identified CCSP-2 expression in 87.0% of colorectal cancer specimens and 89.5% of colon adenoma specimens. Fluorescence imaging of surgical human colon specimens after spraying treatment with the probe permitted a clear distinction of cancer from paired normal colon tissue (target-to-background ratio, 4.09 ± 0.42; P

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White spot syndrome virus (WSSV) is a double-stranded DNA virus that causes severe mortality, leading to great economic loss for cultured shrimp farms. The Manual for Aquatic Animals published by the Office International des Epizooties (OIE, 2012) announced the nested PCR protocol, developed by Lo et al. in 1996 as the standard protocol for WSSV diagnosis. Because current detection tools are prone to carryover contamination and are labor-intensive, an accurate and convenient technique is required. Therefore, the aim of this study was to develop an improved diagnostic PCR method for WSSV that overcomes the known drawbacks of the conventional PCR method. We designed primers directed toward the nucleotide sequence encoding envelope proteins of WSSV, VP19 and VP28. By applying an antisense oligonucleotide technique, we converted this PCR assay into a non-stop one-tube system, subsequently enabling a faster and more sensible PCR assay. In practice, the newly developed protocol detected the WSSV genome from imported frozen shrimps, crabs and bivalves, with a shorter PCR running time and a higher sensitivity compared with other PCR methods.

Traffic Collision Avoidance System (TCAS) is designed to enhance safety in aircraft operations, by reducing the incidences of mid-air collision between aircraft. The current version of TCAS provides only vertical resolution advisory to the pilots, if an aircraft’s collision with another is predicted to be imminent, while efforts to include horizontal resolution advisory have been made, as well. This paper introduces a collision resolution algorithm, which includes both vertical and horizontal avoidance maneuvers of aircraft. Also, the paper compares between the performance of the proposed algorithm and that of algorithms with only vertical or horizontal avoidance maneuver of aircraft.

Multilateration(MLAT) may complement secondary surveillance radar and also act as a real-time backup for the ADS-B system. This System is using time difference of arrival (TDOA) and based on triangulation principle. Each TDOA measurement defines a hyperbola describing possible aircraft locations. The accuracy in MLAT system depends on the positional relationship of the receiver and aircraft. There are various algorithms to localize aircraft based on TOA estimation. In this paper, we use least square method and extended Kalman filter and compare their results. Study results show that the extend Kalman filter provides a better performance than the least square method.

Early remotely-piloted aircraft system (RPAS) development focused on simple reconnaissance to obtain information by visual observation for military demands. Currently, various types of remotely-piloted aircraft (RPA) is being developed worldwide for applications in many different areas. As RPA avionics are combined with CNS/ATM technologies, RPA capabilities will be enhanced and the market is expected to grow rapidly. ICAO has been held the Air Navigation Commission on 14 October 2011 to discuss revising Procedures for air navigation services (PANS) and guidance material related to RPA and their associated systems. It progressed that Annex 2 and 7 will be revised and came into effect from 2012. However most of incorporate revisions are not clear yet. Because the revision articles recommend follow requirements of the state(s). Considering operations of RPA in controlled airspace and between adjacent states, the qualification and training of RPA pilot will be one of the main issues for RPA operation. In this paper, we will take a look at international and domestic trends of regulation framework in ICAO and RPA advanced country in chapter 2.1 and suggest about consideration of remote pilot qualification and training for establishing regulations of remote pilot license.

The recent transition to Performance Based Navigation in aviation enhances the accuracy of aircraft position, safety and efficiency in air traffic operations by using satellite-based navigation system such as GNSS. However, intentional interferences with GNSS signal as well as ones coming from natural phenomena such as solar storm increase. GNSS have very low power and therefore their signals are more susceptible to interferences than ground-based navigation signals. This paper introduces requirements of alternative positioning, navigation and timing(APNT) system and relevant technologies when the GNSS signals are not valid.

In this paper, study the substantial issues which occurs upon free flight environment by performing separation assurance under multiple conflict(over 3 Aircraft), recovery en route under the terms of time constrains and fixed way point after the conflict avoidance, correlations between conflict detection distance and separation assurance by utilizing Autonomous flight algorithm. Result of this experiment demonstrates that the extension of detection distance is advantageous to solution of separation assurance and enhancing of flight efficiency, choose to maneuver by applying time constrain terms and fixed way point according to the situation of conflict prediction in case of recovery maneuver after the conflict avoidance. And separation assurance can be solved by applying 2 degrees or more of bank angle. When choosing the optimal bank angle could be drastically improved flight efficiency.

Airborne separation assurance is a key requirement for Free Flight. This paper is to propose autonomous flight algorithm, such as extended authority of delegation, efficiency of airspace issue to deal with the empirical solution for free flight, and to measure flight efficiency and conflict detection and resolution (CD&R) by utilizing flight performance data under the two circumstances of scenario with the modeling of proposed algorithm and potential field algorithm. The results show that the autonomous flight algorithm is superior to the potential field algorithm under the circumstances of free flight airspace in terms of algorithm performance, CD&R, and flight efficiency.

Edwardsiella tarda is a broadly infectious agent against freshwater and seawater fishes. In the present study, E. tarda specific phage was isolated from fish farms on the west coast of Korea, and the effect of environmental factors such as pH and water temperature on the phage activity was investigated. As a fish model, Nile tilapia (Oreochromis niloticus) was used and the interaction between E. tarda and phage was investigated. The phage activity, in pH test, appeared even higher in seawater than freshwater and was evenly constant up to . The phage and E. tarda were inoculated in tilapia and the phage activity and E. tarda viability were checked on the time intervals. As a result, the number of E. tarda in the group of E. tarda plus phage was constantly reduced to 24 hr post-inoculation compared to the control group without phage, whereas the phage activity was slightly increased in the experiment group. The results suggest that it might be possible to use phage to control the fish disease caused by E. tarda.

Background/Aims: Transarterial chemoembolization (TACE) improves the survival of patients with unresectable hepatocellular carcinoma (HCC) and has been recommended as a first-line therapy for nonsurgical patients with large or multifocal HCC. The long-term outcome of HCC patients receiving TACE prior to hepatic resection is uncertain. Methods: Between January 1997 and December 2007, 1,530 patients underwent hepatic resection for HCC at our center. Thirty-two patients received 1~12 sessions of TACE followed by surgical resection (TACE-surgery group). Their overall and recurrence-free survival rates were compared with those of 64 age- and sex-matched controls who underwent surgery only (surgery group). Overall and recurrence-free survival rates were analyzed. Results: The 1-, 2-, and 5-year overall survival rates did not differ significantly between the TACE-surgery group and the surgery group (78%, 60%, and 26%, respectively, vs. 97%, 83%, and 45%, respectively; P=0.11); however, the 1-, 2-, and 5-year recurrence-free survival rates were significantly lower in the TACE-surgery group than in the surgery group (58%, 36%, and 7%, respectively, vs. 77%, 58%, and 32%, respectively; P=0.01). The distribution of recurrence sites in the TACE-surgery group were intrahepatic in 85.7% and extrahepatic in 14.3%, and did not differ from those in the surgery group (91.4% and 8.6%, respectively; P=0.66). Conclusions: HCC patients who underwent TACE before resection appear to have overall survival rates that are comparable to those without preoperative therapy, although recurrence rates appear to be higher in patients with TACE. (Korean J Hepatol 2010;16:383-388)

C, C1 = centers of masses of the system and the main body E = 3 3 identity matrix H, hw, hp = angular momenta of the system, the wheel, and the pendulum Ĥ = angular momentum of the system as ! 0 Ib, Iw = moments of inertia of the spacecraft main body and wheel J = moment of inertia including main body, wheel, and slosh mass m1, m2 = masses of spacecraft main body and pendulum bob O = pivot point of the pendulum (center of tank location) r = length of massless rod connecting the pendulum bob assumed constant r, ro, rp = position vectors from O to m2, C1 to O, and C1 to m2 ro = distance from C1 to O t = time, s To = frictional torque about O ur, up = r=r and rp=r xiyizi = body-fixed frame having its origin at Ci = momentum wheel torque = viscosity of the liquid fuel , = coordinates of the spherical pendulum = proportionality factor in gyrostat equilibrium equation = ratio of m2 to the total mass, m1 m2 = nutation angle = time duration, s = angular velocity of the momentum wheel !, !e = angular velocities of the spacecraft and the Earth

ELT(Emergency Locator Transmitter) is used to send distress signal in the event of an aircraft crash. It is very useful but the ELT may transmit wrong signal caused by misjudging between crash and hard-landing. The reason of this problem is the low accuracy of the mechanical G-switch currently in use. To improve the ELT, we developed an ELT system using the MEMS(Micro Electro-Mechanical Sensor) accelerometer. The ELT system consists of acceleration data acquisition/analysis system, program of crash recognition, and GPS receiving system for the position information of an aircraft crash site. A free-drop table was developed for verification of the ELT system. The free-drop table was designed to replicate the acceleration and the pulse duration of the hard landing and the crash. By using the free-drop table, we showed that the ELT system performed well.

A CQUISITION techniques by angular momentum exchange have been studied for a long time bymany researchers [1–9]. In this paper, we consider the reorientation of a bias momentum stabilized satellite that is equipped with a momentum wheel and spherical fuel tank. Even though many studies regarding the momentum transfer problem have been done, it appears that none have dealt with it in combination with liquid sloshing. The objective of the present study, then, is to investigate the effect of liquid sloshing on attitude acquisition using a momentum transfer maneuver. In particular, the study focuses on how the viscosity of the liquid and the location of the center of the tank influence the attitude acquisition of the spacecraft. As an equivalent model representing the slosh motion of a liquid, a spherical pendulum is adopted [10,11]. Also, equations of motion for the system composed of three bodies are derived. Results from a digital simulation based on the equations of motion are presented. The spacecraft is assumed to be initially spin stabilized about the axis of the maximummoment of inertia and the wheel spin axis is parallel to the axis of the spacecraft’s intermediate moment of inertia.

The geometric singularity problem is one of principal difficulty when using single-gimbal control moment gyros as spacecraft attitude control devices. To overcome singularity, new steering logics are suggested in this paper which results in a reduction in the difficulty of generating gimbal rates around a singular state. One of the suggested steering laws presented is the reduced dimensional singular value decomposition steering law, which adopts the singular value decomposition in reduced dimensional forms. Two other steering laws make use of the least square method in reduced dimensional forms. All of the suggested steering laws have been generated for the compensation of the torque insufficiency. These logics are verified mathematically and simulations at a singular condition and non-singular condition are performed to see how well they work.

a = transverse component of the system angular momentum C1, C = centers of mass of the main body and the system F = thrust vector (0 0 F3) along the symmetry axis passing through C1 H = angular momentum vector of the system I1, I2, I3 = moments of inertia of the main body about the centroidal principal axes x , y, and z m1, m2 = masses of spacecraft main body and pendulum bob O = pivot point of the pendulum r = length of massless rod connecting the pendulum bob r, rO , rp = position vectors from O to m2, C1 to O, and C1 to m2 r1, r2 = position vectors from C to C1 and m2, respectively xyz = body-fixed frame having its origin at C1 β, βd = resonant and detuned frequencies e = nondimensional small parameter θ , ψ = generalized coordinates of the pendulum θs , θ = stationary point of θ and variation from that point μ = ratio of m2 to the total mass, m1 + m2 σ = parameter describing the nearness of the detuned frequency to the resonance frequency τ = scaled time = angle of rotation of the main body ω = angular velocity of the coordinate system xyz

The attitude instability of a spin-stabilized, thrusting upper stage spacecraft is investigated based on a two-body model consisting of a symmetric main body, representing the spacecraft, and a spherical pendulum, representing the liquefied slag pool entrapped in the aft section of the rocket motor. Exact time-varying nonlinear equations are derived and used to eliminate the drawbacks of conventional linear models. To study the stability of the spacecraft's attitude motion, both the spacecraft and pendulum are assumed to be in states of steady spin about the symmetry axis of the spacecraft and the coupled time-varying nonlinear equation of the pendulum is simplified. A quasi-stationary solution to that equation and approximate resonance conditions are determined in terms of the system parameters. The analysis shows that the pendulum is subject to a combination of parametric and external-type excitation by the main body and that energy from the excited pendulum is fed into the main body to develop the coning instability. When one of the resonance conditions and real flight data are used in the original time-varying nonlinear equations, the results match well with the observed motion before and after motor burnout of typical spin-stabilized upper stages. Some numerical examples are presented to explain the mechanism of the coning angle growth and how disturbance moments are generated.

The attitude motion of a spin-stabilized, upper-stage spacecraft is investigated based on a two-body model, consisting of a symmetric body, representing the spacecraft, and a spherical pendulum, representing the liquid slag pool entrapped in the aft section of the rocket motor. Exact time-varying nonlinear equations are derived and used to eliminate the drawbacks of conventional linear models. To study the stability of the spacecraft`s attitude motion, both the spacecraft and pendulum are assumed to be in states of steady spin about the symmetry axis of the spacecraft and the coupled time-varying nonlinear equation of the pendulum is simplified. A quasi-stationary solution to that equation and approximate resonance conditions are determined in terms of the system parameters. The analysis shows that the pendulum is subject to a combination of parametric and external-type excitation by the main body and that energy from the excited pendulum is fed into the main body to develop the coning instability. In this paper, numerical examples are presented to explain the mechanism of the coning angle growth and how angular momenta and disturbance moments are generated.

An advanced real-time satellite simulator (ARTSS) has been developed to support the ground operations activities of the ETRI satellite control system, such as testing of the system facilities, validation of flight control procedures, verification of satellite commands as well as training of the ground operators. The design of ARTSS is based on the top-down approach and makes use of a modular programming to ensure flexibility in modification and expansion of the system. Graphics-based monitoring and control facilities enhance the satellite simulation environment. The software spacecraft model in ARTSS simulates the characteristics of a geostationary communication satellite using a momentum bias three-axis stabilization control technique. The system can be also interfaced with a hardware payload subsystem such as Ku-band communication transponder to enhance the simulator capability. Therefore, ARTSS is a high fidelity satellite simulation tool that can be used on low-cost desk top computers. In this paper, we describe the design features, the simulation models and the real-time operating functions of the simulator.

A new mathematical model to predict the beam pointing instability of a nonconservative two-body satellite system in spinning injection mode has been developed by using Newton-Euler and projection methods. Since the on-axis and null axis of the omni antenna with toroidal pattern beam form a right angle, wobbling of the antenna on-axis is measured by determining the Euler angles which represent the orientation of the satellite's spin axis. Because of the complexity of the system which is a time varying, nonstationary, nonlinear dynamical system, a numerical method is used for the analysis. Computer simulation results present the effects of the mass distribution and internal mass motion on the antenna beam pointing.

An analytical control law for reorienting a spacecraft that is based on Lyapunov stability theory is discussed. This method is chosen to reduce nutation by minimizing the kinetic energy of the spacecraft. Previous studies of Lyapunov-based control employ weighting coefficients to influence the steady state time; however none of the studies explicitly suggest how to select these values. This paper develops a method to determine the weighting coefficients in terms of known parameters and desired states of the system. The resulting analytical control solution is validated with previous published results, and then used to investigate spacecraft sensitivity to tank location.

The momentum wheel spin-up in spacecraft with partially-filled liquid propellant tanks undergoing a reorientation maneuver results in undesired nutation around the final spin axis. In this study, we investigate the sensitivity of the spacecraft nutation to several design parameters, including momentum wheel spin-up rate, fuel viscosity, and tank location. The goal of the study is to aid in spacecraft design that presents acceptable trade-off between residual angular velocity and acceptable acquisition time. The methods employed include optimization of propellant tank placement to minimize post-maneuver spacecraft nutation while achieving fast acquisition times. The control is achieved through appropriate momentum wheel spin-up strategy that avoids excessive excitation of the system for a given spacecraft configuration. Results from numerical simulations are compared to selected results obtained with an analytical method and show excellent agreement.

Background/Aims Compact lipiodol uptake without enhancement on multiphasic helical computed tomography (CT) has been suggested as a radiologic response criterion in hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE) and subsequent partial hepatectomy. However, its usefulness has not been fully investigated in the explanted liver. Methods Between 1998 and 2007, 81 patients with HCC underwent 1-9 sessions of TACE followed by liver transplantation (LT). Thirty-nine tumors in 29 patients showed a radiologic response on CT performed prior to LT. The radiologic response criteria and the duration of the response were evaluated to predict total necrosis in the explanted liver. Results Among the 39 tumors, 34 nodules (87.2%) exhibited total pathological necrosis. While 13 out of 16 tumors (81.3%) with a radiologic response for 6 months or less were completely necrotic, 21 out of 23 tumors (91.3%) with a radiologic response of longer than 6 months showed total necrosis. Conclusions Our results suggested that the radiologic response criteria based on serial CT images might be useful for predicting total necrosis of TACE-pretreated HCC in LT.

The purpose of the study is to present simple physical and mathematical models of fluid in a tank of the aerospace vehicle such as launch vehicle or missile and to investigate its dynamic stability for a parameter space. The model includes viscosity of the fluid to predict the effect of energy dissipation associated with its slosh and uses a simplified vehicle dynamics which is applicable to ground equivalent model. In this paper, fluid in the container is modeled as two-mass system subject to harmonic excitation and stability boundaries for determination of stable-unstable regions of the motion are obtained by using an analytical method. Also, computer simulations are conducted for various parameter values to verify the analytical results and time histories of motion are compared to explain the effect of variation of parameters of the system.

We tested the hypothesis that angiotensin-converting enzyme (ACE) and angiotensinogen gene polymorphism influence the incidence, development and outcome of preeclampsia. Subjects were recruited from 90 Korean patients with preeclampsia during pregnancy and 98 age-matched controls. After isolation of DNA, polymerase chain reactions (PCR) were carried out to detect polymorphism of the ACE and angiotensinogen. M235T and T174M genotypes of angiotensinogen were determined by digestion with restriction enzyme endonuclease Tth 111-I and NCo I, respectively. The frequency of DD genotype was significantly greater in preeclampsia (0.36) than in controls (0.14) (p0.05). The frequency of D allele was 0.55 in preeclampsia and 0.40 in controls (p0.05). There were no differences in the onset of preeclampsia and pregnancy outcomes according to the ACE genotypes. There was no difference in the frequency of a allele of angiotensinogen M235T between the groups (0.79:0.78 in preeclampsia : controls). The frequency of T allele of angiotensinogen T174M gene was slightly increased, but not significantly, in preeclampsia (0.11) than in controls (0.07). In a multivariate analysis, only ACE genotype was associated with the development of preeclampsia (beta=0.27, p=0.05). In conclusion, a molecular variant of ACE, but not angiotensinogen, gene is associated with preeclampsia in Korean women.