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Antiapoptotic B-cell lymphoma-2 (Bcl-2) proteins suppress apoptosis by interacting with proapoptotic regulators. They commonly contain a hydrophobic groove where the Bcl-2 homology 3 (BH3) domain of Bcl-2 family members or BH3 domain-containing non-Bcl-2 family proteins can be accommodated. Peroxisomal testis-specific 1 (Pxt1) was previously identified as a male germ cell-specific protein whose overexpression causes germ cell apoptosis and infertility in male mice. Sequence and biochemical analyses also showed that human Pxt1, which is composed of 134 amino acids and is longer than mouse Pxt1 consisting of only 51 amino acids, has a BH3 domain that interacts with antiapoptotic Bcl-2 proteins, including Bcl-2 and Bcl-xL. In this study, we determined the crystal structure of Bcl-xL bound to the human Pxt1 BH3 domain. The five BH3 consensus residues are well conserved in the human Pxt1 BH3 domain and make a critical contribution to the complex formation in a canonical manner. Structural and biochemical analyses also demonstrated that Bcl-xL interacts with the BH3 domain of human Pxt1 but not with that of mouse Pxt1, and that residues 76-83 of human Pxt1, absent in mouse Pxt1, play a pivotal role in the intermolecular binding to Bcl-xL. While Bcl-xL consistently colocalized with human Pxt1 in mitochondria, it did not do so with mouse Pxt1, when expressed in HeLa cells. Collectively, these data verified that human and mouse Pxt1 differ in their binding ability to the antiapoptotic regulator Bcl-xL, which might affect their functionality in controlling apoptosis.

In the low-flow rates of off-design conditions in the pump–turbines, complicated flows can develop with vortices in the flow passages, which significantly increase the vibrations and noise, resulting in destabilizing the pump–turbine system. Under low-flow-rate conditions, an appropriate Thoma number is the most essential requirement for stable operation in turbine mode of the pump–turbine. Thus, this study elucidated to examine the internal flow and unsteady pressure phenomena in a laboratory-scale pump–turbine model operated in turbine mode with different Thoma numbers. The experimental investigations were conducted under 70% of the flow rate at the best efficiency point with different Thoma number to observe the unsteady pressures and vortex rope behavior. Then, the numerical validations were conducted by three-dimensional unsteady-state RANS analyses in a SAS–SST model. The Thoma number did not significantly affect the performance of the pump–turbine model or the unsteady flow phenomena in the vaneless and runner regions. However, the Thoma number affected the draft tube region at low flow rate condition. At low Thoma numbers, the irregular flow phenomena along the flow direction enhanced the unsteady pressure characteristics.

The importance of renewable energy will increase rapidly due to the global regulation of carbon dioxide emissions to cope with global warming. However, renewable energy has a high output variation because of the fluctuating characteristics of the energy source. Therefore, pumped-storage power stations require high flexibility and reliability in operation under off-design conditions, especially in the pump mode. When a pump-turbine operates under various part load conditions in pump mode, highly dynamic phenomenon such as stationary vortex and rotating stall occur. The performance characteristics in pump mode are vital for the safe and effective operation. A number of studies have been conducted to investigate the flow characteristics in a turbine or pump mode under different GVOs through numerical simulations. However, the studies about the influence of the position of the interface and the steady and unsteady interface condition on the pump characteristics of pump-turbines have been not completely clear. In this paper, the three-dimensional steady and unsteady Reynolds-averaged Navier–Stokes equations were solved for a detailed analysis of the influence of interface conditions with various guide vane opening conditions in pump mode. To ensure the reliability of the numerical analysis, the numerical results were validated in comparison with the experimental data.

Francis turbines are the most commonly used turbines for hydroelectric power generation. Preliminary studies to verify turbine designs are often performed with small-scale models; however, when the runner blade of a full-size turbine is geometrically scaled down to prepare a model for evaluating the design variables and performance characteristics, the blades become very thin and difficult to manufacture. Hence, the blockage effect of the runner blade should be considered to find a suitable blade thickness that satisfies the required hydraulic performance. Furthermore, a clear understanding of the blockage ratio at the highest efficiency point and off-design condition is required to investigate different blade thicknesses and performance characteristics. Here, the blockage effect of the runner blade on the hydraulic performance and internal flow characteristics of a 300-class Francis hydro turbine was investigated. Three-dimensional Reynolds-averaged Navier–Stokes calculations were performed with a shear stress transport turbulence model to analyze the internal flow characteristics near the runner blade and compare the blockage effect with various blade thicknesses on major performance parameters such as the hydraulic efficiency. Flow analyses for the off-design conditions were also performed with various blade thicknesses. The obtained results indicated that the power and efficiency gradually decreased with increasing blockage ratio. The runner head loss increased due to the mismatches between the flow angle and blade angle with changing the inlet velocity triangle components according to blockage ratio. Especially the efficiency of approximate 3.4% decreased as the blockage ratio increased with 12.5%, compared to the reference model. It was verified that the blockage effect significantly affects the design of Francis turbine models.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with high mortality and infectivity rates in humans since its emergence. Analysis using high-accuracy real-time polymerase chain reaction (PCR) is recommended for the detection of general respiratory viruses including SARS-CoV-2, but it takes a long time (e.g. ~ 6 h); moreover, on-site diagnosis is difficult owing to the need for skilled technicians and advanced laboratory facilities. Currently, the importance of point-of-care testing (POCT) is being emphasized for the rapid detection of SARS-CoV-2. Here, we developed a multiplex real-time reverse transcription PCR (rRT-PCR) analysis that not only detects SARS-CoV-2 but also D614G strains with higher contagiousness than wild types among SARS-CoV-2 mutants using probe-based rRT-PCR. Moreover, this method was applied to portable PCR equipment capable of POCT to confirm high detection sensitivity and specificity. Multiple assays were possible with fluorescence labeling of individual probes. Furthermore, using a microfluidic chip-based point-of-care testing rRT-PCR platform, detection time was reduced by more than half compared with the commonly used detection system. This demonstrates that our assay has 100% of high sensitivity and specificity and could thus aid in the rapid and simple screening of SARS-CoV-2 carrying the mutation. We present a rapid detection method for mutations in SARS-CoV-2.

Double suction centrifugal pumps find their usage in a variety of applications because of their ability to deliver good performance at higher flowrates and heads. The main issue with these devices is the occurrence of large pressure pulsations which cause noise, vibration and unstable operation. The present work makes an effort using steady and unsteady computational fluid dynamics (CFD) approach to minimize these pulsations and also to improve the hydraulic performance of the considered pump. Fast Fourier Transform (FFT) analysis was performed to calculate the amplitude of these pressure pulsations. A parametric study was undertaken to find the effect of impeller stagger angles in reducing these pulsations and finding the most desirable stagger angle. Then, the performance of reference non-staggered impeller design was evaluated with the use of split volute arrangement and its comparison was done with the staggered impeller design. Finally, a combination of staggered impeller design with the split volute arrangement was tested to find its utility in suppressing pressure pulsations. It was observed that the best hydraulic performance could be obtained by the staggered 30° design with reduced pulsations; however, the least pressure pulsations were delivered by the combination of staggered 30° design with the split volute.

The recent studies reported that DNA methylation markers show changes with age, and expected that the DNA methylation markers can be effectively used for estimation of age in forensic genetics. In this study, we applied droplet digital PCR (ddPCR) method to investigate the DNA methylation pattern in the CpG sites, and we constructed an age prediction model based on the ddPCR method. The ddPCR is capable of highly sensitive quantitation of nucleic acid and detection of sequence variations in gene by separating the sample into large number of partitions and clonally amplifying nucleic acids in each partition. We extracted DNA from saliva samples collected from several age groups. The DNA was bisulfite converted and subjected to ddPCR using specifically designed primers and probes. The methylation ratio of each sample was calculated and correlation between the methylation ratio and the chronological age was analyzed. In the results, methylated DNA ratio at the 4 CpG sites (cg14361627, cg14361627, cg08928145 and cg07547549) showed strong correlation with chronological age. Percent-methylation values at 4 CpG markers and chronological ages of the 76 individuals were analyzed by multiple regression analysis, and we constructed an age prediction model. We observed a strong correlation (Spearman’s rho = 0.922) between predicted and chronological ages of 76 individuals with a MAD from chronological age of 3.3 years. Collectively, the result in this study showed the potential applicability of ddPCR to predict age from saliva.

Cytosolic protein tyrosine phosphatase epsilon (cyt-PTPε) plays a central role in controlling differentiation and function of osteoclasts, whose overactivation causes osteoporosis. Based on our previous study reporting a number of cyt-PTPε inhibitory chemical compounds, we carried out a further and extended analysis of our compounds to examine their effects on cyt-PTPε-mediated dephosphorylation and on osteoclast organization and differentiation. Among five compounds showing target selectivity to cyt-PTPε over three other phosphatases in vitro, two compounds exhibited an inhibitory effect against the dephosphorylation of cellular Src protein, the cyt-PTPε substrate. Moreover, these two compounds caused destabilization of the podosome structure that is necessary for the bone-resorbing activity of osteoclasts, and also attenuated cellular differentiation of monocytes into osteoclasts, without affecting cell viability. Therefore, these findings not only verified anti-osteoclastic effects of our cyt-PTPε inhibitory compounds, but also showed that cyt-PTPε expressed in osteoclasts could be a putative therapeutic target worth considering.

Understanding and predicting vortex-induced motion (VIM) of offshore systems for deep seawater applications is crucial to improve the system safety and integrity. We report on experimental tow-tank measurements and numerical simulations of VIM of a deep-draft offshore platform, specifically Paired-Column Semisubmersible (PC-Semi). The study is carried out in model scale (1:54), at subcritical flow regime with Re∼104. Motion of the floating structure has three degrees of freedom: in-line, cross-flow, and yaw. Large periodic cross-flow motion is measured for headings 0°, 11.25°, and 22.5°, for reduced velocities ( U r ) between 5 and 10. Considerably smaller cross-flow amplitude is recorded at 45° heading across the Ur range considered. An extensive sensitivity study is performed using computational fluid dynamics (CFD) to capture the transient displacement history of VIM (in-line, cross-flow, and yaw motion components). Amplitude and period of cross-flow (transverse) motion are obtained from statistical analysis of VIM time history and subsequently used as the validation criterion between the CFD simulation and the model tests. Satisfactory agreement between the CFD results and tow-tank measurements is achieved with a Delayed Detached Eddy Simulation – Shear Stress Transport (DDES-SST) formulation. This work provides experimental results and serves as a practical starting point to set up a CFD problem to estimate amplitude and period of cross-flow VIM motion for offshore engineering applications.

The tidal currents in the region of South-Western sea of Korea can be utilized for the development of tidal current power, benefiting many fishing nurseries and nearby islands. Furthermore, it can contribute to promoting energy independent islands. This study focuses on floating-bridge type small tidal current turbine, which can be installed between the small islands limited space unlike large tidal current turbines. The aim is to develop a floating-bridge type 15 kW-class small horizontal axis tidal current turbine. As part of the research for the reduced model experiment of hydrofoils, a 50 W-class horizontal axis tidal current turbine model was investigated. Therefore, for this study, blade design was carried out using two different hydrofoils (MNU26 and NACA63421). Performance and hydrodynamic characteristics are investigated by using computational fluid dynamics and experimental methods. Among the two blades, NACA63421 blade showed the best power coefficient at low Reynolds number, whereas MNU26 blade performed better for higher Reynolds number. The MNU26 hydrofoil was applied to the blade design from the previous study. The MNU26 hydrofoil has a 26% thickness in contrast to the NACA63421, which has a 21% thickness. This indicates that the MNU26 can be applied throughout the blade length for the 15 kW-class turbine whilst providing good structural strength.

The current work presents experimental and computational investigations of fluid flow through a 37 element CANDU nuclear fuel bundle. Experiments based on Magnetic Resonance Velocimetry (MRV) permit three-dimensional, three-component fluid velocity measurements to be made within the bundle with sub-millimeter resolution that are non-intrusive, do not require tracer particles or optical access of the flow field. Computational fluid dynamic (CFD) simulations of the foregoing experiments were performed with the hydra-th code using implicit large eddy simulation, which were in good agreement with experimental measurements of the fluid velocity. Greater understanding has been gained in the evolution of geometry-induced inter-subchannel mixing, the local effects of obstructed debris on the local flow field, and various turbulent effects, such as recirculation, swirl and separation. These capabilities are not available with conventional experimental techniques or thermal-hydraulic codes. The overall goal of this work is to continue developing experimental and computational capabilities for further investigations that reliably support nuclear reactor performance and safety.

In this paper, high-order numerical methods are investigated in a system analysis-like code. The classical Welander oscillatory natural circulation problem, which resembles a simplified example for many types of natural circulation loops widely seen in nuclear reactor systems, was chosen to illustrate the applicability of such methods in system analysis codes, and to demonstrate the advantages of such methods over the low-order methods widely used in existing system analysis codes. As originally studied by Welander, the fluid motion in a differentially heated fluid loop can exhibit stable, weakly unstable, and strongly unstable modes. A theoretical stability map has also been originally derived from the stability analysis. Numerical results obtained in this paper show very good agreement with Welander's theoretical derivations. For stable cases, numerical results from both the high-order and low-order numerical methods agree well with the non-dimensional flow rate that were analytically derived. The high-order numerical methods give much less numerical errors compared to those using low-order numerical methods. For stability analysis, the high-order numerical methods perfectly predicted the stability map even with coarse mesh and large time step, while the low-order numerical methods failed to do so unless very fine mesh and time step are used. The result obtained in this paper is a strong evidence for the benefits of using high-order numerical methods over the low-order ones, when they are applied to simulate natural circulation phenomenon that has already gained increasing interests in many existing and advanced nuclear reactor designs.

A red-emitting SrGe 3.99 Mn 0.01 O 9 (SGO:Mn 4+ ) phosphor have been prepared by a solid-state reaction. The structural and optical properties of SGO:Mn 4+ phosphors, together with their thermal quenching property have been investigated. The 3 d electrons of Mn 4+ at octahedral sites of the SGO host showed a crystal field splitting Dq of 2380 cm −1 and Racah parameters, B and C of 1970 and 860 cm −1 , respectively. Due to the 4 A 2g → 4 T 1g and 4 A 2g → 2 T 2g transitions, broad photoluminescence excitation bands were observed at the spectral region spanning from ultraviolet to blue light. The transition from 2 E g to 4 A 2g results in a sharp emission peak at 655 nm. When the yellow-emitting Y 3 Al 5 O 12 :Ce 3+ and red-emitting SGO:Mn 4+ phosphors were incorporated into a blue light-emitting diode (LED), the fabricated white LED showed an emission in the natural white light region with an excellent color rendering index of 92 and a color stability against an increase in the forward current. Thus, SGO:Mn 4+ can be a potential red-emitting phosphor in the fabrication of white LEDs.

This research examines the concentration of radiolysis species (H2, O2, and H2O2) over the porous crud layer using a three dimensional time dependent solute transport model. A Monte Carlo random walk technique is adopted to simulate the transport behavior of the different species with various parametric studies of source term, crud thickness, and crud porosity. Particularly, this model employs a system of coupled mass transport and chemical interactions as the source term, which makes the problem non-linear. It is demonstrated that a negligible effect on radiolysis species concentrations change due to the consideration of source term. The crud thickness and porosity effect on the concentration distributions are notably observed. In general, higher concentration starts from the intersection of the heating surface with the chimney wall from the beginning and it reaches the equilibrium state within tens of seconds. The concentration profiles of the radiolysis species H2, O2, and H2O2 can be directly related to corrosion issues. The direct application of this study to nuclear engineering research is to aid in the design of reactors with higher performance without experiencing an Axial Offset Anomaly (AOA), an unexpected measured shift in axial power distribution from predicted values.

Micro hydro turbines are getting renewed research interest in recovering unused energy from systems like water supply pipelines, sewage treatment and transportation plants, chemical and oil refineries, etc. and making them energy efficient for sustainable development. The present work dealt with this aspect wherein the unused energy of the hot water transportation pipelines, which was earlier throttled by pressure differential control valve (PDCV), was harvested and used elsewhere. A special class of multi-purpose micro hydro turbine known as the positive displacement turbine was developed for the present application which involved very low flow rates with high heads and very low specific speeds and to replace the PDCV which was frequently failing due to cavitation causing loss of energy. A framework was developed for designing such turbines and predicting their performance using CFD. The reasons for the occurrence of cavitation and flow pulsations were also examined and remedial measures were incorporated for their elimination. At the rated condition during experimental study, the base design generated 7.31 kW power with an overall efficiency of 67.7%. The socio-economic analysis was also carried out which concluded that the PDT will aid in energy conservation and reduction in CO2 emissions.

This paper presents the results of an integrated chemical effects experiment of head loss across the sump pump screen with fibrous debris bed over a non-prototypical 10-day post-LOCA incident window. The corrosion head loss experiments (CHLE) is a reduced scaled integral effects testing facility built at the University of New Mexico (UNM) to investigate potential chemical effects on head loss across prepared fibrous debris beds. The results in this paper come from two integral effect tests performed at UNM in order to determine the chemical effects on head loss induced by a zinc source effect and an aluminum precipitation effect (T3: without Zn source case, T4: with Zn source case in containment). The tests were performed with a large surface area of aluminum coupons in the testing facility for an extended period of elevated temperature to accelerate corrosion above that expected under prototypical conditions. These conditions were sufficient to force aluminum precipitation to occur and induce the onset of chemical effects on debris bed head loss. The head loss behavior on two different types of fiber debris beds (blender-processed and NEI-processed debris bed) was evaluated in this study. It was found that the blender-processed bed is much more sensitive in filtering than the NEI-processed bed and consequently had a much higher head loss value across the beds. Aluminum precipitation was observed, with aluminum concentration and turbidity measurements, to form starting on day 7 in Test T3 and on day 6 in Test T4. The onset of aluminum precipitation-induced head loss increase was observed in a similar time frame in both CHLE T3 and T4 tests. In addition, the results of surface analysis (XPS, SEM-EDS) for the tested fiberglass bed are presented.

In this study, sub-cooled flow boiling critical heat flux tests at low pressure were conducted in a rectangular flow channel with one uniformly heated surface, using simulant fluid R-134a as coolant. The experiments were conducted under the following conditions: (1) inlet pressure ( P ) of 400–800 kPa, (2) mass flux ( G ) of 124–248 kg/m 2 s, (3) inlet sub-cooling enthalpy (Δ H i ) of 12–26 kJ/kg. Parametric trends of macroscopic system parameters ( G , P , Δ H i ) were examined by changing inlet conditions. Those trends were found to be generally consistent with previous understandings of CHF behavior at low pressure condition (i.e. reduced pressure less than 0.2). A fluid-to-fluid scaling model was utilized to convert the test data obtained with the simulant fluid (R-134a) into the prototypical fluid (water). The comparison between the converted CHF of equivalent water and CHF look-up table with same operation conditions were conducted, which showed good agreement. Furthermore, the effect of surface wettability on CHF was also investigated by applying atmospheric pressure plasma (AP-plasma) treatment to modify the surface characteristic. With AP-plasma treatment, the change of microscopic surface characteristic was measured in terms of static contact angle. The static contact angle was reduced from 80° on original non-treated surface to 15° on treated surface. An enhancement of 18% on CHF values under flow boiling conditions were observed on AP-plasma treated surfaces compared to those on non-treated heating surfaces.

Synchrophasor measurements can significantly enhance the monitorability of the power grid by revealing the dynamics of grid operation. However, due to high-rate samples collected in large volume, big data challenges emerge to efficiently process the data. The present work advocates robust subspace approaches including robust principal component analysis and subspace clustering, to identify low-dimensional structures in the synchrophasor data, even when portions of measurements are missing due to sensor or network issues, and outliers are present in the data. The outliers can model abnormal dynamics or cyber-attacks in the grid. Numerical tests using simulated synchrophasor data illustrate the utility of the approaches.

A method is proposed for the subtle control of multifunctional nanoparticles by applying an external magnetic field to induce a 1D assembly. Au coated Fe 3 O 4 core–shell nanoparticles (Fe 3 O 4 @Au NPs) were used to fabricate conducting magnetoplasmonic nanochains (MPNCs). Fe 3 O 4 @Au NPs were synthesized in an aqueous solution by a one-step reaction, showing superparamagnetic property, and were well-dispersed and stable in water at physiological pH. The MPNCs were prepared on a solid substrate through magnetic-field-induced alignment of Fe 3 O 4 @Au NPs. The dimension of these MPNCs is simply controlled by adjusting magnetic field strength. In order to utilize MPNCs as sensing platform, an annealing step was performed to improve their electrical properties. The annealed MPNCs were used as electrical transducers for DNA detection by successively immobilizing DNA probe on MPNCs and hybridizing them with target DNA. A direct detection of the electrical changes was performed using linear sweep voltammetry (LSV). A significant resistance increase was observed upon hybridization of the target DNA to the probe DNA on MPNCs.

MicroRNA (miRNA) plays an important role in various diseases and in cellular and molecular responses to toxicants. In the present study, we investigated differential expression of miRNAs in response to three triazole fungicides (myclobutanil, propiconazole, and triadimefon). The human hepatoma cell line (HepG2) was treated with the above triazoles for 3 h or 48 h. miRNA-based microarray experiments were carried out using the Agilent human miRNA v13 array. At early exposure (3h), six miRNAs were differentially expressed and at late exposure (48 h), three miRNAs were significantly expressed. Overall, this study provides an array of potential biomarkers for the above triazole fungicides. Furthermore, these miRNAs induced by triazoles could be the foundation for the development of a miRNA-based toxic biomarker library that can predict environmental toxicity.

Henöch-Schönlein purpura nephritis (HSPN) is considered a systemic form of immunoglobulin A nephropathy (IgAN). Although these are different pictures of a single disease, there are no studies directly comparing long-term outcomes of these two clinical entities. To clarify this, we studied 120 patients with biopsy-proven HSPN and 1070 patients with IgAN. The primary outcome was the composite of a doubling of baseline serum creatinine, end-stage renal disease, or death. Secondary outcomes included the individual renal outcomes or the rate of decline in estimated glomerular filtration rate. In the unmatched cohort, patients with HSPN had more vasculitic symptoms, more favorable histologic features, and were more commonly treated with steroids than patients with IgAN. The risk of reaching the primary outcome was significantly lower in HSPN patients than patients with IgAN (hazard ratio, 0.67). The 1:2 propensity score matching gave matched pairs of 89 patients with HSPN and 178 patients with IgAN, resulting in no differences in baseline conditions. In this matched cohort, there were no significant differences in reaching the primary and secondary outcomes between the two groups. Thus, after adjustment by propensity score matching, clinical outcomes did not differ between HSPN and IgAN, suggesting the two forms of the same disease have a similar prognosis.

This paper reports a micro/nano dual-scaled artificial lotus leaf that is formed on a silicon substrate by simple and inexpensive fully nonlithographic approach, combining a sandblasting technique and an anodic aluminum oxidation (AAO) process. The proposed dual-scaled surface was demonstrated by covering the sandblasted micro-roughened substrate entirely with nano-scale protuberances, and its surface wettability was characterized by measuring the static contact angle (SCA) and contact angle hysteresis (CAH). The measurements confirmed that the proposed dual-scaled surface can sufficiently ensure superhydrophobicity in the Cassie wetting regime with a high SCA of 159.4 ± 0.5° and a low CAH of 3.9 ± 0.7°, and the surface wetting properties can be improved greatly compared to those of flat, sandblasted micro-roughened and nano-scale protuberance-arrayed surfaces. Through a dropping test, it was observed that the fabricated dual-scaled surface can ensure its superior water-repellency with various levels of the impact velocity. Finally, a self-cleaning ability of the proposed dual-roughened surface was verified experimentally by observing the dynamic rolling-off behavior of the water droplet on the surface covered with contaminants.

Left atrial (LA) volume index (LAVI) has been considered a stable indicator of diastolic dysfunction and an independent predictor of mortality in patients with end-stage renal disease. To date, however, little is known about the relationship between LA enlargement and the changes in residual renal function (RRF).This study was undertaken to investigate the association between LA enlargement and the decline in RRF in 121 incident peritoneal dialysis patients. Within 2 months after the initiation of peritoneal dialysis, LA enlargement was determined by echocardiography and RRF by 24-hour urine collection. Subsequently, RRF was measured every 6 months.The rates of decline in RRF were significantly greater in patients with LA enlargement (LAVI32 mL/m(2)) compared with those without LA enlargement (-0.17 ± 0.18 vs -0.07 ± 0.16 mL/min/month/1.73 m(2), P = .002). In a linear mixed model, there was a significant difference in the rates of RRF decline over time between patients with and without LA enlargement (P.001). Pearson's correlation analysis revealed that there were significant inverse correlations between the rates of the decline in RRF and LAVI (r = -0.22, P = .018). In multiple linear regression analysis adjusted for other risk factors, LAVI was found to be an independent determinant of the rates of decline in RRF (β = -0.026, P = .018).This study shows that a higher LAVI is independently associated with a more rapid decline in RRF in patients with end-stage renal disease on peritoneal dialysis.

We present three nuclear/hydrogen-related R&D activities being performed at KAIST: air-ingressed LOCA analysis code development, gas turbine analysis tool development, and hydrogen-production system analysis model development. The ICE numerical technique widely used for the safety analysis of water-reactors is successfully implemented into GAMMA, with which we solve the basic equations for continuity, momentum conservation, energy conservation of the gas mixture, and mass conservation of 6 species (He, N2, O2, CO, CO2, and H2O). GAMMA has been extensively validated using data from 14 test facilities. We developed a tool to predict the characteristics of HTGR helium turbines based on the throughflow calculation with a Newton- Raphson method that overcomes the weakness of the conventional method based on the successive iteration scheme. It is found that the current method reaches stable and quick convergence even under the off-normal condition with the same degree of accuracy. The dynamic equations for the distillation column of HI process are described with 4 material components involved in the HI process: H2O, HI, I2, H2. For the HI process we improved the Neumann model based on the NRTL (Non-Random Two-Liquid) model. The improved Neumann model predicted a total pressure with 8.6% maximum relative deviation from the data and 2.5% mean relative deviation, and liquid-liquid-separation with 9.52% maximum relative deviation from the data.

In mammalian cells, the DNA damage-related histone H2A variant H2A.X is characterized by a C-terminal tyrosyl residue, Tyr-142, which is phosphorylated by an atypical kinase, WSTF. The phosphorylation status of Tyr-142 in H2A.X has been shown to be an important regulator of the DNA damage response by controlling the formation of gammaH2A.X foci, which are platforms for recruiting molecules involved in DNA damage repair and signaling. In this work, we present evidence to support the identification of the Eyes Absent (EYA) phosphatases, protein-tyrosine phosphatases of the haloacid dehalogenase superfamily, as being responsible for dephosphorylating the C-terminal tyrosyl residue of histone H2A.X. We demonstrate that EYA2 and EYA3 displayed specificity for Tyr-142 of H2A.X in assays in vitro. Suppression of eya3 by RNA interference resulted in elevated basal phosphorylation and inhibited DNA damage-induced dephosphorylation of Tyr-142 of H2A.X in vivo. This study provides the first indication of a physiological substrate for the EYA phosphatases and suggests a novel role for these enzymes in regulation of the DNA damage response.

We developed an improved thermo-physical model for the hydrogen–iodide (HI) VLE and decomposition behavior in the iodine–sulfur (IS) cycle. We reproduced the Neumann's modified NRTL model by an optimization scheme from the experimental data that he used. Then, we improved the model by correcting his unphysical assumption for the non-randomness parameter, and used the two-step equilibrium approach for the HI decomposition modeling. The KAIST model (improved Neumann's model) with a new set of binary parameters predicts the total pressure of HI solution within 2.98% of RMS error for the HI–H 2 O binary mixture, and within 7% of RMS error for the HI–H 2 O–I 2 ternary mixture. We also proposed a simple logic to predict the liquid–liquid phase separation condition within 2.07% of relative deviation in the temperature range of 70–149 °C.

We searched for the optimal compromised operating conditions for the Bunsen reaction of IS thermochemical water splitting, considering the key concerns of the IS cycle: the liquid–liquid equilibrium (LLE) phase separation performance, the characteristics of water distribution between the sulfuric acid (SA) phase and the poly-hydroiodic acid ( HI x ) phase, side reaction occurrence, and the effect on operating costs. Experimental data available from a literature survey were combined, and common trends were examined through a series of parametric studies. Based on the results, the optimal operating point and allowable operating window for the Bunsen reaction have been proposed: the optimal point is represented by 4 mol of excess iodine and 11 mol of excess water in the stoichiometry at temperature of 330 K, while the allowable window ranges over 4 – 6 mol for the excess iodine, 11 – 13 mol for the excess water, and 330 – 350 K for the temperature. After the Bunsen reaction and LLE phase separation, 5 mol of the excess water is distributed to the SA phase and 6 – 8 mol to the HI x phase. Operating within this window makes it possible to avoid the side reaction and iodine solidification, to increase the HI concentration well above the azeotropic point in the HI x section, and to minimize operating costs arising from excess iodine and water.

The flow diverted bed (FDB) system was developed to improve the stream water quality. This system (Run 2) had two wetlands where the flow from the upper layer (aerobic) in the first wetland could be redirected to the lower layer (anaerobic) in the second wetland by the flow diverter, and vice versa. In addition, the yellow-soil media placed at the bottom layer allowed a larger influx in the lower layer and had a sorption capacity of phosphate ions. The removal efficiencies of COD and TN at Run 2 [hydraulic loading rate (HLR) = 177 cm/d] was 1.7–3.6 times higher than that at Run 1 (HLR = 192 cm/d) without the diverter. The values of void fraction, dimensionless variance, dispersion number, Peclet number and velocity for this system were found to be 0.6637, 0.2847, 0.1717, 5.8241, and 53.2 m/d, respectively. The reducing trend of each pollutant was exponentially decreased along the overall length of this system. Also, the transport was dominated by convection (plug flow) rather than dispersion (complete mix). The volumetric removal rate constants for COD, SS, TKN, TN, and TP were found to be 4.854, 7.988, 1.388, 1.625, and 1.767 d −1 via the first-order rate model. Consequently, the flow diverter and yellow-soil media in this system played an important role in enhancing the treatability of pollutants and operating at a higher HLR.

MAP kinase phosphatase 5 (MKP5) is a member of the mitogen-activated protein kinase phosphatase (MKP) family and selectively dephosphorylates JNK and p38. We have determined the crystal structure of the catalytic domain of human MKP5 (MKP5-C) to 1.6 A. In previously reported MKP-C structures, the residues that constitute the active site are seriously deviated from the active conformation of protein tyrosine phosphatases (PTPs), which are accompanied by low catalytic activity. High activities of MKPs are achieved by binding their cognate substrates, representing substrate-induced activation. However, the MKP5-C structure adopts an active conformation of PTP even in the absence of its substrate binding, which is consistent with the previous results that MKP5 solely possesses the intrinsic activity. Further, we identify a sequence motif common to the members of MKPs having low catalytic activity by comparing structures and sequences of other MKPs. Our structural information provides an explanation of constitutive activity of MKP5 as well as the structural insight into substrate-induced activation occurred in other MKPs.

A series of rhodanine derivatives was synthesized and evaluated for their ability to inhibit PRL-3. Benzylidene rhodanine derivative showed good biological activity, while compound 5e was the most active in this series exhibiting an IC50 value of 0.9 microM in vitro and showed a reduced invasion in cell-based assay.

Optically active N -formyl- N -hydroxy-α-phenylalanine methylamide ( 1 ) and N -formyl- N -hydroxy-β-phenylalanine methylamide ( 2 ) were evaluated as inhibitors for thermolysin (TLN) to find that while the d -form is more potent than its enantiomer in the case of the hydroxamate of α-Phe-NHMe, in the inhibition with hydroxamate of β-Phe-NHMe, the l -isomer ( K i =1.66±0.05 μM) is more effective than its enantiomer. In order to shed light on the stereochemical preference observed in the inhibitions, X-ray crystallographic analyses of the crystalline TLN· d - 1 and TLN· l - 2 complexes were performed to the resolution of 2.1 A. While l - 2 binds TLN like substrate does with its benzyl aromatic ring occupying the S 1 ′ pocket, the electron density in the S 1 ′ pocket in the complex of TLN· d - 1 is weak and could best be accounted for by the methylcarbamoyl moiety. For both inhibitors, the hydroxamate moiety coordinates the active site zinc ion in a bidentate fashion.

Serpin (serine protease inhibitor) proteins are involved in diverse physiological processes including inflammation, coagulation, matrix remodeling, and cell differentiation. Deficiency of normal serpin functions leads to various hereditary diseases. Besides their clinical importance, serpin proteins draw much attention due to the large conformational changes that occur upon interaction with proteases. We present here the crystal structure of an uncleaved alpha(1)-antitrypsin determined by the multiple isomorphous replacement method and refined to 2.1 A resolution. The structure, which is the first active serpin structure based on experimental phases, reveals novel conformations in the flexible loops, including the proximal hinge region of the reactive center loop and the surface cavity region in the central beta-sheet, sheet A. The determined loop conformation explains the results of recent mutagenesis studies and provides detailed insights into the protease inhibition mechanism. The high-resolution structure of active alpha(1)-antitrypsin also provides evidence for the existence of localized van-der-Waals strain in the central hydrophobic core.

We have investigated the effects of alkaline oxide additives such as Na2O, K2O and Li2O on the microstructure and humidity sensitivity of MgCr2O4TiO2. The addition of Na2O and K2O, especially Na2O, helps to reduce the pore size through the formation of very small soluble phases, which consequently improves the humidity-sensing characteristics, such as the sensitivity, linearity and hysteresis. However, Li2O causes grain overgrowth and consequently the formation of large pores, leading to poor humidity sensitivity.

The bacterial thermoalkalophilic lipases optimally hydrolyze saturated fatty acids at elevated temperatures. They also have significant sequence homology with staphylococcal lipases, and both the thermoalkalophilic and staphylococcal lipases are grouped as the lipase family I.5. We report here the first crystal structure of the lipase family I.5, the structure of a thermoalkalophilic lipase from Bacillus stearothermophilusL1 (L1 lipase) determined at 2.0-A resolution. The structure is in a closed conformation, and the active site is buried under a long lid helix. Unexpectedly, the structure exhibits a zinc-binding site in an extra domain that accounts for the larger molecular size of the family I.5 enzymes in comparison to other microbial lipases. The zinc-coordinated extra domain makes tight interactions with the loop extended from the C terminus of the lid helix, suggesting that the activation of the family I.5 lipases may be regulated by the strength of the interactions. The unusually long lid helix makes strong hydrophobic interactions with its neighbors. The structural information together with previous biochemical observations indicate that the temperature-mediated lid opening is triggered by the thermal dissociation of the hydrophobic interactions.