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Several preclinical studies demonstrate that antitumor efficacy of programmed cell death-1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade can be improved by combination with other checkpoint inhibitors. Lymphocyte-activation gene 3 (LAG-3) is an inhibitory checkpoint receptor involved in T cell exhaustion and tumor immune escape. Here, we describe ABL501, a bispecific antibody targeting LAG-3 and PD-L1 in modulating immune cell responses against tumors. ABL501 that efficiently inhibits both LAG-3 and PD-L1 pathways enhances the activation of effector CD4

Encapsulating platinum nanoparticles with a carbon shell can increase the stability of core platinum nanoparticles by preventing their dissolution and agglomeration. In this study, the synthesis mechanism of a platinum core-carbon shell catalyst via thermal reduction of a platinum-aniline complex was investigated to determine how the carbon shell forms and identify the key factor determining the properties of the Pt core-carbon shell catalyst. Three catalysts originating from the complexes with different platinum to carbon precursor ratios were synthesized through pyrolysis. Their structural characteristics were examined using various analysis techniques, and their electrochemical activity and stability were evaluated through half-cell and unit-cell tests. The relationship between the nitrogen to platinum ratio and structural characteristics was revealed, and the effects on the electrochemical activity and stability were discussed. The ratio of the carbon precursor to platinum was the decisive factor determining the properties of the platinum core-carbon shell catalyst.

We prepared Nafion composite membranes by impregnating Nafion-212 with polydopamine, poly(sulfonated dopamine), and poly(dopamine

Cobalt–iron sulfides supported on N-doped carbon were synthesized as energy storage material using ball milling followed by carbonization. As-synthesized materials were structurally analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. Furthermore, cobalt–iron sulfides supported on N-doped carbon were coated on Ni foam, and their electrochemical performance was tested in a 3-M KOH electrolyte. The as-fabricated Co–Fe–S-2 electrode registered a specific capacitance of 1252 F g−1 at 1 A g−1 and also showed capacitance retention of 66.4% at 20 A g−1. In addition, asymmetric supercapacitors (ASC) were fabricated using the as-synthesized electrode materials and it had a voltage window of 0–1.6 V. Among them, the activated carbon (AC)//Co–Fe–S-2 ASC device showed maximum specific capacitance of 169.3 F g−1 at 1 A g−1, and it registered maximum energy density of 59.6 Wh kg−1 at power density of 0.796 kW kg−1. The AC//Co–Fe–S-2 device delivered a rate capability of 55.6% at 30 A g−1, and it reveals a capacitance retention of 76.3% over 5000 cycles. Herein we also found that ball-milling-assisted synthesis of Co–Fe–S-2 electrode material is a promising candidate for high-performance ASCs.

An efficient synthesis of nitrogen and sulfur co-doped graphene-like carbon sheets from coir pith bio-waste through the mechanical activation method is reported in this study. The structural characterization reveals the presence of a graphene-like carbon sheet, which is uniformly doped with nitrogen and sulfur atoms in a carbon network. The nitrogen and sulfur co-doped graphene-like carbon sheets (NSG) has amorphous nature with a defective porous carbon structure and it depicts the maximum specific capacitance of 247.1 F g−1 at 0.2 A g−1 and a capacitance retention of 75.2% at 10 A g−1. The synthesized NSG-10 registered a maximum energy density of 33.6 Wh kg−1 at 0.2 A g−1 and shows the maximum power density of 4220.0 W kg−1 at 10.0 A g−1. Furthermore, a symmetric supercapacitor (SSC) device shows the device capacitance of 33.7 F g−1 at 0.2 A g−1 when operated at 1.0 V. The SSC device gives a capacitance retention of 82.0% at 10 A g−1 and reveals an excellent stability with no losses in capacitance with 100% columbic efficiency over 10,000 cycles. The results suggest that the proposed methodology is a simple and unique way to synthesize heteroatoms-doped graphene-like carbon sheets from biomass materials for a supercapacitor.

Background Metabolic syndrome is associated with cardiovascular diseases and is characterized by insulin resistance. Recent studies suggest that the triglyceride/high-density lipoprotein cholesterol (TG/HDLC) ratio predicts insulin resistance better than individual lipid levels, including TG, total cholesterol, low-density lipoprotein cholesterol (LDLC), or HDLC. We aimed to elucidate the relationship between the TG/HDLC ratio and metabolic syndrome in the general Korean population. Methods We evaluated the data of adults ≥20 years old who were enrolled in the Korean National Health and Nutrition Examination Survey in 2013 and 2014. Subjects with angina pectoris, myocardial infarction, stroke, or cancer were excluded. Metabolic syndrome was defined by the harmonized definition. We examined the odds ratios (ORs) of metabolic syndrome according to TG/HDLC ratio quartiles using logistic regression analysis (SAS ver. 9.4; SAS Institute Inc., Cary, NC, USA). Weighted complex sample analysis was also conducted. Results We found a significant association between the TG/HDLC ratio and metabolic syndrome. The cutoff value of the TG/HDLC ratio for the fourth quartile was ≥3.52. After adjustment, the OR for metabolic syndrome in the fourth quartile compared with that of the first quartile was 29.65 in men and 20.60 in women (P

With emerging stability issues in fuel cell technology, a non-conventional catalyst not supported on carbon materials has been highlighted because it can avoid negative influences of carbon support materials on the stability, such as carbon corrosion. The nanostructured thin film catalyst is representative of non-conventional catalysts, which shows improved stability, enhanced mass specific activity, and fast mass transfer at high current densities. However, the nanostructured thin film catalyst usually requires multi-step processes for fabrication, making its mass production complex and irreproducible. We introduce a Pt-Cu alloy nanostructured thin film catalyst, which can be simply prepared by electrodeposition. By using hydrogen bubbles as a template, a three-dimensional free-standing foam of Cu was electrodeposited directly on the micro-porous layer/carbon paper and it was then displaced with Pt by simple immersion. The structure characterization revealed that a porous thin Pt-Cu alloy catalyst layer was successfully formed on the micro-porous layer/carbon paper. The synthesized Pt-Cu alloy catalyst exhibited superior durability compared to a conventional Pt/C in single cell test.

The deep space orbit determination software (DSODS) is a part of a flight dynamic subsystem (FDS) for the Korean Pathfinder Lunar Orbiter (KPLO), a lunar exploration mission expected to launch after 2018. The DSODS consists of several sub modules, of which the orbit determination (OD) module employs a weighted least squares algorithm for estimating the parameters related to the motion and the tracking system of the spacecraft, and subroutines for performance improvement and detailed analysis of the orbit solution. In this research, DSODS is demonstrated and validated at lunar orbit at an altitude of 100 km using actual Lunar Prospector tracking data. A set of a priori states are generated, and the robustness of DSODS to the a priori error is confirmed by the NASA planetary data system (PDS) orbit solutions. Furthermore, the accuracy of the orbit solutions is determined by solution comparison and overlap analysis as about tens of meters. Through these analyses, the ability of the DSODS to provide proper orbit solutions for the KPLO are proved.

We present simulations of the optical-band images of high-redshift galaxies utilizing 845 near-ultraviolet (NUV) images of nearby galaxies obtained through the Galaxy Evolution Explorer (GALEX). We compute the concentration (C), asymmetry (A), Gini (G), and M20 parameters of the GALEX NUV/Sloan Digital Sky Survey r-band images at z ~ 0 and their artificially redshifted optical images at z = 0.9 and 1.6 in order to quantify the morphology of galaxies at local and high redshifts. The morphological properties of nearby galaxies in the NUV are presented using a combination of morphological parameters, in which earlytype galaxies are well separated from late-type galaxies in the G–M20, C–M20, A–C, and A–M20 planes. Based on the distribution of galaxies in the A–C and G–M20 planes, we examine the morphological K-correction (i.e., cosmological distance effect and bandshift effect). The cosmological distance effect on the quantitative morphological parameters is found to be significant for early-type galaxies, while late-type galaxies are more greatly affected by the bandshift effect. Knowledge of the morphological K-correction will set the foundation for forthcoming studies on understanding the quantitative assessment of galaxy evolution.

The current study designs the mission orbit of the lunar CubeSat spacecraft to measure the lunar local magnetic anomaly. To perform this mission, the CubeSat will impact the lunar surface over the Reiner Gamma swirl on the Moon. Orbit analyses are conducted comprising ΔV and error propagation analysis for the CubeSat mission orbit. First, three possible orbit scenarios are presented in terms of the CubeSat’s impacting trajectories. For each scenario, it is important to achieve mission objectives with a minimum ΔV since the CubeSat is limited in size and cost. Therefore, the ΔV needed for the CubeSat to maneuver from the initial orbit toward the impacting trajectory is analyzed for each orbit scenario. In addition, error propagation analysis is performed for each scenario to evaluate how initial errors, such as position error, velocity error, and maneuver error, that occur when the CubeSat is separated from the lunar orbiter, eventually affect the final impact position. As a result, the current study adopts a CubeSat release from the circular orbit at 100 km altitude and an impact slope of 15°, among the possible impacting scenarios. For this scenario, the required ΔV is calculated as the result of the ΔV analysis. It can be used to practically make an estimate of this specific mission’s fuel budget. In addition, the current study suggests error constraints for ΔV for the mission.

This paper presents an overview of deep space orbit determination software (DSODS), as well as validation and verification results on its event prediction capabilities. DSODS was developed in the MATLAB object-oriented programming environment to support the Korea Pathfinder Lunar Orbiter (KPLO) mission. DSODS has three major capabilities: celestial event prediction for spacecraft, orbit determination with deep space network (DSN) tracking data, and DSN tracking data simulation. To achieve its functionality requirements, DSODS consists of four modules: orbit propagation (OP), event prediction (EP), data simulation (DS), and orbit determination (OD) modules. This paper explains the highest-level data flows between modules in event prediction, orbit determination, and tracking data simulation processes. Furthermore, to address the event prediction capability of DSODS, this paper introduces OP and EP modules. The role of the OP module is to handle time and coordinate system conversions, to propagate spacecraft trajectories, and to handle the ephemerides of spacecraft and celestial bodies. Currently, the OP module utilizes the General Mission Analysis Tool (GMAT) as a third-party software component for highfidelity deep space propagation, as well as time and coordinate system conversions. The role of the EP module is to predict celestial events, including eclipses, and ground station visibilities, and this paper presents the functionality requirements of the EP module. The validation and verification results show that, for most cases, event prediction errors were less than 10 millisec when compared with flight proven mission analysis tools such as GMAT and Systems Tool Kit (STK). Thus, we conclude that DSODS is capable of predicting events for the KPLO in real mission applications.

The enantioselective synthesis of quaternary carbon stereocenters and application to natural products has been a formidable challenge to synthetic organic chemists. Ways to quaternary stereocenters are demanded very much given the prevalence of the centers in various attractive natural products. One of the most promising methods for the purpose is the Pd-catalyzed alkylation of prochiral stabilized enolates. Although these methods have been useful, regioselectivity can be meet only in the case of single acidic site or a large pKa difference between two acidic sites to prevent the mixture formation. Instead, Tsuji allylation pathway from allyl enol carbonates which would be formed regioselectively by controlled methods prevented the production of mixtures of allylated products and allowed the neutral reaction conditions to yield good to excellent selectivity. Recently, we published the stereoselective synthesis of (-)mesembrane 1 which contains a quarternary center. Mesembrane 1 is a well known member of the Sceletium alkaloids, which has the basic structural element of cis-3a-aryloctahydroindole skeleton 2 (Figure 1). In the previous synthesis, we have applied desymmetrization of 1,3-dicarbonyl groups of cyclohexadione by intramolecular condensation with chiral amides. The maximum selectivity was moderately 3:1. So, we wanted to find out the strategy which would afford enhanced selectivity, and decided to combine Tsuji asymmetric allylation and the resoluting condensation step using a proper chiral auxilary. In the condensation step, it is anticipated that the energy difference of the diastereomeric aminol intermediates formed from attack of chiral amide to carbonyl group presumably would cause the difference of formation rates and the final production yields. We should find out the matching chiral auxiliary which would result in optimum resolution in the cyclization process to afford the desired isomer with better selectivity (Scheme 1). First, in the condensation reaction of chiral amide and carbonyl group of 7, we wanted to see how much resoluting selectivity would be generated through diastereomeric aminol intermediate (Table 1). The inseparable amide ketone diastereomers 7 could be prepared by employing the known procedure from 3. Cyclization has been found to proceed best in toluene at 65 C in the presence of TsOH. Among four chiral auxiliaries selected for the preparation of 7, two (Entry 1 and 2) provided 2:1 selectivity in 50 and 70% yields. Although the selectivity was moderate, we expected that this step would be helpful to increase the selectivity as an ancillary step and provide a known chiral intermediate. We have tried asymmetric allylation of allyl enol carbonate 9 to find out the optimum condition including the best chiral ligand. The required intermediate 9 was prepared from 3 by the reaction with allyl chloroformate in 67% yield as a single isomer. Various reaction conditions have been adopted in the allylation reaction using several known chiral ligands. And we found that (R,R)-ANDEN-phenyl Trost ligand 11 (5.5 mol %) afforded the best selectivity 83:17 in 58% yield in toluene at −78 C in the presence of Pd2(dba)3 (2.5 mol %). The isomeric ratio was determined by chiral HPLC column chromatography (Scheme 2). At this stage the absolute configuration of the quarternary center could not be determined

Generally, In-Wheel motor system consists of suspension, steering, electric motor, friction brake, and wheel and varies with the combination structure of each component. However, the key point of In-Wheel motor system to be applied in small electric vehicle is the integration capability to meet the requirements such as wheel space, power performance, strength of components and so on. This paper describes integration methodology for In-Wheel motor system on the rear axle with the consideration of the restricted wheel space and unsprung mass. In addition, optimization of the motor housing is performed to improve mass and strength of the In-Wheel motor housing according to the test specification of weight transfer from the tire patch. It is found from the results that the prototype In-Wheel motor system meets the vehicle performances and strength requirements.

We present a comprehensive catalog of 700 confirmed star clusters in the field of M31 compiled from three major existing catalogs. We detect 418 and 257 star clusters in Galaxy Evolution Explorer (GALEX) near-ultraviolet (NUV) and far-ultraviolet (FUV) imaging, respectively. Our final catalog includes photometry of star clusters in up to 16 passbands ranging from FUV to NIR as well as ancillary information such as reddening, metallicity, and radial velocities. In particular, this is the most extensive and updated catalog of UV integrated photometry for M31 star clusters. Ages and masses of star clusters are derived by fitting the multi-band photometry with model spectral energy distribution (SED); UV photometry enables more accurate age estimation of young clusters. Our catalog includes 182 young clusters with ages less than 1 Gyr. Our estimated ages and masses of young clusters are in good agreement with previously determined values in the literature. The mean age and mass of young clusters are about 300 Myr and 10^4 M_sun, respectively. We found that the compiled [Fe/H] values of young clusters included in our catalog are systematically lower (by more than 1 dex) than those from recent high-quality spectroscopic data and our SED fitting result. We confirm that most of the young clusters kinematics show systematic rotation around the minor axis and association with the thin disk of M31. The young clusters distribution exhibits a distinct peak in the M31 disk around 10 - 12 kpc from the center and follow a spatial distributions similar to other tracers of disk structure such as OB stars, UV star-forming regions, and dust. Some young clusters also show concentration around the ring splitting regions found in the southern part of the M31 disk and most of them have systematically younger (< 100 Myr) ages., 67 pages, 22 figures, accepted for publication in ApJS

MEA (Membrane Electrode Assembly) consisting of the electrodes coated with a catalyst and the membrane is the most important in fuel cell. In fabricating MEA, there are two ways to coat catalyst depending on a coating substrate, i.e. CCM (Catalyst Coated Membrane, coating on membrane), and CCS (Catalyst Coated Substrate, coating on carbon paper). Generally, CCM is known as a better way than CCS, and spray coating has been widely used for CCM method. In this study, CCM method was also adopted to make MEA, however, catalyst was coated sonochemically to introduce a new catalyst coating method in making MEA. The most convincing and famous mechanism known for a sonochemical metal ion reduction is a reduction of metal precursor by radicals generated by hot spot during ultrasound irradiation1. Thus we introduced ultrasound irradiation for synthesizing and coating of platinum on membrane simultaneously. In applying ultrasound irradiation, we changed experimental conditions such as time of radiation and the intensity of radiation. The amount of platinum loaded on membrane was proportion to the time and the power of ultrasound irradiation as shown in Fig. 1. The solution used for platinum electrode formation includes not only platinum precursor but also a reducing agent and a surfactant to help precursor reduction. After Pt catalyst coating, remaining impurities like a reducing agent and a surfactant were removed by using stirring in pure water. In order to check whether platinum was successfully loaded on membrane, FE-SEM (Field Emission Scanning Electron Microscope) and EDS (Energy Dispersive x-ray Spectroscopy) analyses were carried out as shown in Fig. 2, and it proved the effectiveness of ultrasound irradiation in making platinum electrode on membrane. Furthermore, we looked into the electrochemical characteristics of the MEA using CV (Cyclic Voltammertry) and EIS (Electrochemical Impedance Spectroscopy), and then the result was compared with that of a conventional MEA. MEAs, both new and conventional, were made into single cells for a performance test and a comparison. In making a single cell with the MEA made by ultrasound irradiation, ionomer effect was thoroughly studied to take advantage of thin thickness of platinum catalyst layer. It is known that the mass transfer through thin film catalyst layer is fast without ionomer2. In thus presentation, all the results investigated in the study will be presented with in-depth discussion. References: 1. J. H. Bang and K. S. Suslick, Adv. Mater., 22, 1039 (2010). 2. A. K. Schmoeckel, G. D. Vernstrom, R. Atanasoski, and M. K. Debe, J. Power Sources, 161, 1002 (2006).