120 results on '"Sul S"'
Search Results
2. Mode switching DFIG for low voltage ride through
- Author
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Sul, S K, Wei, Feng, Vilathgamuwa, Don, Sul, S K, Wei, Feng, and Vilathgamuwa, Don
- Abstract
With the rapid development of world-wide wind energy generation using doubly fed induction generations (DFIGs), low voltage ride through (LVRT) has become a great concern. This paper focuses on a unique topology of DFIG called IG connection mode to help the DFIG ride through grid faults smoothly. Transient analysis of IG connection mode is carried out to derive the generator currents. With this analysis, the control strategy for IG connection mode DFIG was developed. From the simulation results, it is clearly visible that IG mode could work in both normal and low grid voltage conditions. Simulation results clearly show that the DFIG with the proposed mode switching control could smoothly ride through low voltage grid faults while satisfying grid code requirements.
- Published
- 2011
3. A hybrid cascaded multilevel inverter with supercapacitor direct integration for wind power systems
- Author
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Sul, S K, Jayasinghe, S.D., Vilathgamuwa, Don, Udaya, Udaya, Sul, S K, Jayasinghe, S.D., Vilathgamuwa, Don, and Udaya, Udaya
- Abstract
This paper presents a grid-side inverter based supercapacitor direct integration scheme for wind power systems. The inverter used in this study consists of a conventional two-level inverter and three H-bridge modules. Three supercapacitor banks are directly connected to the dc-links of H-bridge modules. This approach eliminates the need for interfacing dc-dc converters and thus considerably improves the overall efficiency. However, for the maximum utilization of super capacitors their voltages should be allowed to vary. As a result of this variable voltage space vectors of the hybrid inverter get distributed unevenly. To handle this issue, a modified PWM method and a space vector modulation method are proposed and they can generate undistorted current even in the presence of unevenly distributed space vectors. A supercapacitor voltage balancing method is also presented in this paper. Simulation results are presented to validate the efficacy of the proposed scheme, modulation methods and control techniques.
- Published
- 2011
4. MCTs and IGBTs - A comparison of performance in power electronic circuits
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Sul, S. K, Profumo, F, Cho, G. H, and Lipo, T. A
- Subjects
Electronics And Electrical Engineering - Abstract
There is a continuous demand for improvements in the quality of switching power devices, such as higher switching frequency, higher withstand voltage capability, larger current-handling capability, and lower conduction losses. However, for single-conduction-mechanism devices (SCRs, GTOs, BJTs, FETs), possessing all these features is probably unrealizable for physical reasons. An attractive solution appears to be double-mechanism devices, in which the features of both a minority carrier device (BJT or SCR) and a majority carrier device (MOSFET) are embedded. Both IGBTs (insulated-gate bipolar transistors) and MCTs (MOS-controlled thyristors) belong to this family of double-mechanism devices and promise to have a major impact on converter circuit signs. The authors deal with the major features of these two devices, pointing out those that are most critical to the design of converter topologies. In particular, the two devices have been tested both in a chopper and in two resonant link converter topologies, and the experimental results are reported.
- Published
- 1989
5. Performance testing of a high frequency link converter for Space Station power distribution system
- Author
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Sul, S. K, Alan, I, and Lipo, T. A
- Subjects
Electronics And Electrical Engineering - Abstract
The testing of a brassboard version of a 20-kHz high-frequency ac voltage link prototype converter dynamics for Space Station application is presented. The converter is based on a three-phase six-pulse bridge concept. The testing includes details of the operation of the converter when it is driving an induction machine source/load. By adapting a field orientation controller (FOC) to the converter, four-quadrant operation of the induction machine from the converter has been achieved. Circuit modifications carried out to improve the performance of the converter are described. The performance of two 400-Hz induction machines powered by the converter with simple V/f regulation mode is reported. The testing and performance results for the converter utilizing the FOC, which provides the capability for rapid torque changes, speed reversal, and four-quadrant operation, are reported.
- Published
- 1989
6. Online Minimum-Copper-Loss Control of an Interior Permanent-Magnet Synchronous Machine for Automotive Applications
- Author
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Jeong, Y., primary, Sul, S., additional, Hiti, S., additional, and Rahman, K.M., additional
- Published
- 2006
- Full Text
- View/download PDF
7. Novel Antiwindup of a Current Regulator of a Surface-Mounted Permanent-Magnet Motor for Flux-Weakening Control
- Author
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Kwon, T.-S., primary and Sul, S.-K., additional
- Published
- 2006
- Full Text
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8. Control of Rubber Tyred Gantry Crane With Energy Storage Based on Supercapacitor Bank
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Kim, S.-M., primary and Sul, S.-K., additional
- Published
- 2006
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- View/download PDF
9. A New Method of Partial Excitation for Dual Moving Magnet Linear Synchronous Motor
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Kwak, M.-S., primary and Sul, S.-K., additional
- Published
- 2004
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10. Fast Initial Pole-Position Estimation for Non-Salient PM-LSM Based on Agreement of Two Reference Frames.
- Author
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Kozo Ide, Hyun-Soo Song, Takaki, M., Morimoto, S., and Ki-Sul, S.
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- 2006
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11. Adaptive Flux Observer with On-line Inductance Estimation of an IPMSM Considering Magnetic Saturation.
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Jeong, Y. and Sul, S.
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- 2005
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12. Analysis and prediction of inverter switching frequency in direct torque control of induction machine based on hysteresis bands and machine parameters
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Kang, J.-W., primary and Sul, S.-K., additional
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- 2001
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13. MCTs and IGBTs: a Comparison of Performance in Power Electronic Circuits
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Sul, S. K., Profumo, Francesco, Cho, G. H., and Lipo, T. A.
- Published
- 1989
14. Online MTPA Operation of IPMSM Based on Dual-Loop Control in Polar Coordinates
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Hyeon-Sik Kim and Sul, S. -K
15. Initial rotor position estimation of an interior permanent magnet synchronous machine using carrier-frequency injection methods
- Author
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Jeong, Y., primary, Lorenz, R.D., additional, Jahns, T.M., additional, and Sul, S., additional
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16. Adaptive Flux Observer with On-line Inductance Estimation of an IPMSM Considering Magnetic Saturation
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Jeong, Y., primary and Sul, S., additional
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17. Maximum torque control of an induction machine in the field weakening region
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Kim, S.-H., primary, Sul, S.-K., additional, and Park, M.-H., additional
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18. Initial rotor position estimation of an interior permanent magnet synchronous machine using carrier-frequency injection methods.
- Author
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Jeong, Y., Lorenz, R.D., Jahns, T.M., and Sul, S.
- Published
- 2003
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19. Maximum torque control of an induction machine in the field weakening region.
- Author
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Kim, S.-H., Sul, S.-K., and Park, M.-H.
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- 1993
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20. Analysis of shaft torsional vibration in inverter-fed induction motor drive systems.
- Author
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Hong, C.-O. and Sul, S.-K.
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- 1993
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21. Speed sensorless vector control of an induction motor using an extended Kalman filter.
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Kim, Y.-R., Sul, S.-K., and Park, M.-H.
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- 1992
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22. A load commutated inverter-fed induction motor drive with a novel DC-side commutation circuit.
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Mok, H.-S., Sul, S.-K., and Park, M.-H.
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- 1992
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23. A novel three-phase quasi-resonant DC link inverter.
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Lee, J.-W., Sul, S.-K., and Park, M.-H.
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- 1991
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24. Implementation and Sensorless Vector-Control Design and Tuning Strategy for SMPM Machines in Fan-Type Applications
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Parag Kshirsagar, Alessandro Lidozzi, Dushan Boroyevich, Seung-Ki Sul, Jihoon Jang, Rolando Burgos, Fred Wang, P., Kshirsagar, R. P., Burgo, J., Jang, Lidozzi, Alessandro, F., Wang, D., Boroyevich, Seung Ki, Sul, Kshirsagar, P, Burgos, Rp, Jihoon, J, Wang, F, Boroyevich, D, and Sul, S. K.
- Subjects
Electronic speed control ,Engineering ,Vector control ,business.industry ,Synchronizing ,Control engineering ,Industrial and Manufacturing Engineering ,Phase-locked loop ,Control and Systems Engineering ,Control theory ,Control system ,State observer ,Electrical and Electronic Engineering ,business ,Pulse-width modulation - Abstract
This paper presents a complete design methodology for the sensorless vector control of permanent magnet synchronous machine (PMSM) motor drives in fan-type applications. The proposed strategy is built over a linear asymptotic state observer used to estimate the PMSM back-EMF, and a novel tracking controller based on a phase-locked loop (PLL) system, which by synchronizing the estimated and actual d-q frames estimates the rotor speed and position. The paper presents the complete derivation of all associated control-loops, namely state observer, tracking controller, d-q axes current regulator, speed controller, an anti-saturation control loop - which provides inherent operation in the flux-weakening region, and all corresponding anti-windup loops. Detailed design rules are provided for each of these loops, respectively verified through time-domain simulations, frequency-response analysis, and experimental results using a 300 Vdc 3.5 kW PMSM PWM motor-drive, validating both the design methodology and the excellent performance attained by the proposed control strategy
- Published
- 2012
25. Design and Evaluation of a PLL-Based Position Controller for Sensorless Vector Control of Permanent-Magnet Synchronous Machines
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Rolando Burgos, Dushan Boroyevich, Alessandro Lidozzi, Parag Kshirsagar, Pedro Rodriguez, Fred Wang, Seung-Ki Sul, Jihoon Jang, Burgos, Rp, Kshirsagar, P, Lidozzi, Alessandro, Jangg, J, Wang, F, Boroyevich, D, Rodriguez, P, and Sul, S. K.
- Subjects
Engineering ,Vector control ,business.industry ,Rotor (electric) ,Synchronizing ,Control engineering ,Converters ,law.invention ,Phase-locked loop ,Control theory ,law ,Control system ,Feedback linearization ,business - Abstract
This paper presents a rotor position controller for sensorless vector control of permanent magnet synchronous machines (PMSM) based on a synchronous d-q frame phase-locked loop (PLL). Extending the capabilities of PLL's for grid-connected converters?using feedback linearization to ensure a constant dynamic response regardless of the operating region and rotor speed, the proposed controller takes advantage of the sinusoidal and balanced PMSM back-EMF voltages synchronizing the estimated and actual d-q frames. The resultant controller structure is readily linearized providing an accurate design tool based on frequency response specifications. A complete design procedure is provided, together with simulation and experimental results with a 3.5 kW PMSM drive, all of which verify the excellent results attained by the proposed PLL-based position controller.
- Published
- 2006
26. Mechanism of stable lithium plating and stripping in a metal-interlayer-inserted anode-less solid-state lithium metal battery.
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Ko DS, Kim S, Lee S, Yoon G, Kim D, Shin C, Kim D, Lee J, Sul S, Yun DJ, and Jung C
- Abstract
To reliably operate anode-less solid-state Li metal batteries, wherein precipitated Li acts as the anode, stabilizing the interface between the solid electrolyte and electrode is crucial. The interface can be controlled by a metal interlayer on the electrolyte to form a Li alloy buffer that facilitates stable Li plating/stripping, thereby mitigating the loss of physical contact and preventing short circuits. However, the mechanism governing stable Li plating/stripping in the metal interlayer without degrading battery materials remains unclear owing to an incomplete understanding of the dynamic and complex electrochemical reactions in the solid state. Through multiple operando and post-mortem analyses of the Li deposition behavior in the morphology, chemistry and microstructure, a close correlation is found between the Li-metal alloying process with the microstructural evolution and electrochemical performance when Ag, Au, Zn, and Cu interlayers were adopted on the garnet-type solid electrolyte Li
6.5 La3 Zr1.5 Ta0.5 O12 . The Ag interlayer improved the interfacial stability enabled by Ag-dissolved Li, which inhibited dendritic growth, passing through the phase-separated Li-Ag alloy microstructure, while the other metals did not because of the Li plating at the Li-metal alloy/solid electrolyte interface. This work provides fundamental guidance for material selection and interface design, advancing the development of anode-less solid-state batteries., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)- Published
- 2025
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27. Striatal-hippocampal functional connectivity contributes to real-life positive anticipatory experiences and subjective well-being.
- Author
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Shin WG, Jyung M, Choi JA, Choi I, and Sul S
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- Humans, Female, Male, Young Adult, Adult, Neural Pathways physiology, Corpus Striatum physiology, Corpus Striatum diagnostic imaging, Personal Satisfaction, Brain Mapping methods, Ecological Momentary Assessment, Reward, Magnetic Resonance Imaging methods, Anticipation, Psychological physiology, Hippocampus physiology, Hippocampus diagnostic imaging
- Abstract
Positive anticipatory experiences are key to daily well-being. However, the brain's functional architecture underlying real-world positive anticipatory experiences and well-being remains unexplored. In the present study, we combined an ecological momentary assessment and resting-state functional neuroimaging to identify the neural predictors of real-world positive anticipatory experiences and explore their relationships with subjective well-being (SWB). With a model-based approach, we quantified participants' accuracy in predicting positive events and the degree to which participants' affective states were influenced by the positive anticipation. We found that individuals with higher accuracy in predicting upcoming positive events showed greater SWB, and this relationship was mediated by greater positive anticipatory feelings. Importantly, functional connectivity of the dorsal and ventral striatal-hippocampal networks significantly predicted the accuracy and positive anticipatory feelings, respectively. These functional networks were further predictive of SWB. Our findings provide novel and ecologically valid evidence that the interaction between neural systems for reward-processing and memory plays an important role in real-life positive anticipatory experiences and everyday SWB., (© The Author(s) 2024. Published by Oxford University Press.)
- Published
- 2024
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28. A streamlined algorithm for two-dimensional bandgaps and defect-state energy variations in InGaN-based micro-LEDs.
- Author
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Ko DS, Lee S, Park J, Sul S, Jung C, Yun DJ, Kim MK, Lee J, Choi JH, Park SY, Shim M, Son WJ, and Kim SY
- Abstract
Bandgaps and defect-state energies are key electrical characteristics of semiconductor materials and devices, thereby necessitating nanoscale analysis with a heightened detection threshold. An example of such a device is an InGaN-based light-emitting diode (LED), which is used to create fine pixels in augmented-reality micro-LED glasses. This process requires an in-depth understanding of the spatial variations of the bandgap and its defect states in the implanted area, especially for small-sized pixelation requiring electroluminescence. In this study, we developed a new algorithm to achieve two-dimensional mappings of bandgaps and defect-state energies in pixelated InGaN micro-LEDs, using automated electron energy-loss spectroscopy integrated with scanning transmission electron microscopy. The algorithm replaces conventional background subtraction-based methods with a linear fitting approach, enabling enhanced accuracy and efficiency. This novel method offers several advantages, including the independent calculation of the defect energy ( E
d ) and bandgap energy ( Eg ), reduced thickness effects, and improved signal-to-noise ratio by eliminating the need for zero-loss spectrum calibration. These advancements allow us to reveal the relationship between the bandgap, defect states, microstructure, and electroluminescence of the semiconductor under ion-implantation conditions. The streamlined analysis achieves a spatial resolution of approximately 5 nm and an exceptional detection limit. Additionally, ab initio calculations indicate gallium vacancies as the predominant defects.- Published
- 2024
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29. Motivational and behavioral mechanisms underlying generalized health risking behaviors during the COVID-19 pandemic in smokers.
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Park J, Lee S, Gu X, Fiore VG, Sul S, and Chung D
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- Humans, Male, Female, Adult, Middle Aged, Smoking psychology, SARS-CoV-2, Health Behavior, Public Health, Young Adult, Aged, COVID-19 psychology, COVID-19 epidemiology, Motivation, Smokers psychology, Health Risk Behaviors, Pandemics
- Abstract
Under the threat of public health challenges such as the recent COVID-19 pandemic, individual citizens' active and cooperative participation in precautionary measures is crucial. Although non-compliance is recognized as a recurring problem, it remains unknown why some individuals tend to comply less than others and whether violations of preventive behaviors are observed consistently across different public health issues. To test our hypothesis that individuals would show consistent public health behavior transcending domains, we collected self-reports from two independent samples of participants (total N = 2983) on health risk beliefs and behavioral choices. Participants' responses were collected in regard to two separate yet closely related public health issues: smoking and the COVID-19 pandemic. Our data reveal that on average, individuals' beliefs and behaviors are consistent across different public health domains. In particular, smokers showed diminished compliance behaviors during the pandemic, which was mediated by their lower motives to protect public health. These results provide a psychological mechanism of how individuals' health risk behaviors are generalized across different public health domains that may explain why some individuals (here, current-smokers) are more prone to violate public health behaviors., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)
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- 2024
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30. Specificity of Amino Acid Profiles Produced in Soybean Fermentations by Three Bacillus spp.
- Author
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Seo S, Jeong DW, Sul S, and Lee JH
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- Bacillus subtilis metabolism, Bacillus subtilis growth & development, Bacillus licheniformis metabolism, Bacillus licheniformis growth & development, Sodium Chloride metabolism, Proteolysis, Salt Tolerance, Glycine max microbiology, Amino Acids metabolism, Bacillus metabolism, Fermentation
- Abstract
We compared the salt tolerance and proteolytic activity of 120 strains of each of Bacillus subtilis , Bacillus velezensis , and Bacillus licheniformis . Most B. subtilis strains exhibited growth in 12% (w/v) NaCl and showed proteolytic activity in 10% or 11% NaCl. The majority of B. velezensis strains grew in 14% NaCl and showed proteolytic activity in 12% or 13% NaCl. Most B. licheniformis strains grew in 14% NaCl and exhibited proteolytic activity in 5%-7% NaCl. We selected nine representative strains of each species based on their proteolytic activities and analyzed the free amino acid (FAA) profiles produced by culture of the bacteria on soybean. Statistical analyses of the 22 FAAs quantified in the cultures revealed clustering of FAA production profiles at the species level. The FAA production profiles of B. subtilis and B. velezensis were similar, and both differed from that of B. licheniformis . These trends persisted in cultures containing 7% NaCl. These results suggest that FAA production profiles are characteristic of each Bacillus species. Specifically, in soybean cultures compared with uninoculated soybeans, B. subtilis increased the amounts of leucine and phenylalanine; B. velezensis increased the amounts of leucine, phenylalanine, and tyrosine; and B. licheniformis increased the amounts of alanine, glutamic acid, tyrosine, and ornithine, and dramatically decreased the amount of arginine. The proteolytic activity of B. velezensis strains correlated with the quantity of FAAs in their soybean cultures. Considering its salt tolerance and proteolytic activity, B. velezensis showed high potential for contributing to the ripening of high-salt fermented soybean foods. Our results regarding the specific production of amino acids at the species level and correlations between proteolytic activities and produced amino acid quantities will facilitate the determination and selection of target strains for functional Bacillus -fermented foods.
- Published
- 2024
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31. Obstetric and Perinatal Outcomes in 44,118 Singleton Pregnancies: Endometrial Preparation Methods for Frozen-Thawed Embryo Transfer.
- Author
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Yu EH, Lee HJ, Lee S, Kim J, Kim SC, Joo JK, and Na YJ
- Subjects
- Humans, Female, Pregnancy, Adult, Sperm Injections, Intracytoplasmic, Databases, Factual, Abortion, Spontaneous epidemiology, Cryopreservation, Postpartum Hemorrhage, Embryo Transfer methods, Pregnancy Outcome, Fertilization in Vitro, Endometrium pathology
- Abstract
Background: This study aimed to investigate the obstetric and perinatal outcomes of singleton deliveries following frozen embryo transfer (FET) cycles using different endometrial preparation methods., Methods: We analyzed data on 44,118 singleton pregnant women who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI), resulting in delivery or abortion, from the South Korean National Health Insurance Service database. Stratification was based on the type of embryo transfer, viz. fresh embryo transfer and FET cycles, using International Classification of Diseases (Tenth Revision) diagnostic codes, national procedural codes, and prescription medication data within the IVF/ICSI pregnancy cohort. FET was subcategorized into artificial cycle-FET (AC-FET), natural cycle-FET (NC-FET), and stimulated cycle-FET (SC-FET) for comparative analyses of the pregnancy, obstetric, and perinatal outcomes., Results: AC-FET was associated with higher risks of hypertensive disorders of pregnancy, preeclampsia, placenta accreta, and postpartum hemorrhage compared with NC-FET; the risk of macrosomia showed no significant differences. SC-FET was associated with a lower risk of miscarriage and higher rate of term birth beyond 37 weeks compared with NC-FET. However, SC-FET was associated with elevated risks of gestational hypertension and postpartum hemorrhage when compared to NC-FET., Conclusion: The rate of adverse obstetric and perinatal outcomes was higher in AC-FET compared to NC-FET, highlighting NC-FET as a valuable option owing to better maternal and fetal safety. In cases where NC-FET is not feasible, SC-FET presented as a favorable alternative, exhibiting lower miscarriage rates than NC-FET and better obstetric outcomes than AC-FET., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2024 The Korean Academy of Medical Sciences.)
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- 2024
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32. Metal Cocatalyst Engineering in Metal-Semiconductor Hybrid Photocatalysts Achieves a Fivefold Enhancement of Hydrogen Evolution.
- Author
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Park B, Park WW, Choi JY, Bang K, Kim S, Choi YJ, Sul S, Kwon OH, and Song H
- Abstract
This study explores the optimal morphology of photochemical hydrogen evolution catalysts in a one-dimensional system. Systematic engineering of metal tips on precisely defined CdSe@CdS dot-in-rods is conducted to exert control over morphology, composition, and both factors. The outcome yields an optimized configuration, a Au-Pt core-shell structure with a rough Pt surface (Au@r-Pt), which exhibits a remarkable fivefold increase in quantum efficiency, reaching 86 % at 455 nm and superior hydrogen evolution rates under visible and AM1.5 G irradiation conditions with prolonged stability. Kinetic investigations using photoelectrochemical and time-resolved measurements demonstrate a greater extent and extended lifetime of the charge-separated state on the tips as well as rapid water reduction kinetics on high-energy surfaces. This approach sheds light on the critical role of cocatalysts in hybrid photocatalytic systems for achieving high performance., (© 2024 Wiley-VCH GmbH.)
- Published
- 2024
- Full Text
- View/download PDF
33. Correlation between fetal subcutaneous fat thickness and insulin resistance through cord blood analysis immediately after delivery.
- Author
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Lee S, Kim HJ, Lee HJ, Yu EH, Yoon HJ, and Kim SC
- Subjects
- Humans, Female, Pregnancy, Adult, Ultrasonography, Prenatal, Infant, Newborn, Insulin blood, Case-Control Studies, Fetus diagnostic imaging, Cesarean Section, Insulin Resistance, Fetal Blood chemistry, Fetal Blood metabolism, Diabetes, Gestational blood, Subcutaneous Fat diagnostic imaging, Blood Glucose analysis, Blood Glucose metabolism
- Abstract
Objectives: This study aimed to determine whether fetal subcutaneous tissue (SCT) thickness, measured using ultrasound immediately before and after delivery, can reflect changes in glucose metabolism immediately after delivery. We also evaluated the impact of insulin resistance changes during pregnancy by comparing pregnant women with well-controlled gestational diabetes mellitus (GDM) and those with normal glucose metabolism., Study Design: The study participants were 117 pregnant women, including 97 controls and 20 patients with GDM who visited our obstetric clinic between February and December 2022. The participants were scheduled for cesarean delivery at a gestational age of ≥37 weeks. SCT thickness before delivery was measured using ultrasound and within 48 h after delivery using Holtain calipers. The glucose and insulin concentrations were quantified from cord blood collected immediately after delivery. Based on these results, a Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) was performed to assess insulin resistance. Independent t-test or Wilcoxon rank-sum test for continuous variables and Fisher's exact test for categorical variables were used to compare the various parameters. Correlations among the variables in each group were assessed by calculating the correlation coefficient (Pearson's correlation)., Results: SCT thickness measured using ultrasound and calipers demonstrated a strong correlation where pregnant women with GDM exhibited thicker fetal SCT and neonate skinfolds than in those without GDM. Glucose and insulin levels in the cord blood were significantly elevated (p < 0.05) in the gestational diabetic group, along with remarkable differences (p < 0.001) in HOMA-IR. These variables indicated a higher prevalence of glucose intolerance in the neonates of mothers with GDM. In pregnant women with GDM, there was a statistically significant correlation between fetal abdominal SCT thickness and glucose levels (r = 0.64, p < 0.01) and HOMA-IR (r = 0.48, p < 0.05)., Conclusions: Measuring the subcutaneous fat thickness of the fetus shortly before delivery is beneficial for predicting insulin resistance in neonates. This is considered particularly useful for women with effectively managed GDM, where the presence of conditions such as macrosomia may not be pronounced., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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34. The International Climate Psychology Collaboration: Climate change-related data collected from 63 countries.
- Author
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Doell KC, Todorova B, Vlasceanu M, Bak Coleman JB, Pronizius E, Schumann P, Azevedo F, Patel Y, Berkebile-Wineberg MM, Brick C, Lange F, Grayson SJ, Pei Y, Chakroff A, van den Broek KL, Lamm C, Vlasceanu D, Constantino SM, Rathje S, Goldwert D, Fang K, Aglioti SM, Alfano M, Alvarado-Yepez AJ, Andersen A, Anseel F, Apps MAJ, Asadli C, Awuor FJ, Basaglia P, Bélanger JJ, Berger S, Bertin P, Białek M, Bialobrzeska O, Blaya-Burgo M, Bleize DNM, Bø S, Boecker L, Boggio PS, Borau S, Borau S, Bos B, Bouguettaya A, Brauer M, Brik T, Briker R, Brosch T, Buchel O, Buonauro D, Butalia R, Carvacho H, Chamberlain SAE, Chan HY, Chow D, Chung D, Cian L, Cohen-Eick N, Contreras-Huerta LS, Contu D, Cristea V, Cutler J, D'Ottone S, De Keersmaecker J, Delcourt S, Delouvée S, Diel K, Douglas BD, Drupp MA, Dubey S, Ekmanis J, Elbaek CT, Elsherif M, Engelhard IM, Escher YA, Etienne TW, Farage L, Farias AR, Feuerriegel S, Findor A, Freira L, Friese M, Gains NP, Gallyamova A, Geiger SJ, Genschow O, Gjoneska B, Gkinopoulos T, Goldberg B, Goldenberg A, Gradidge S, Grassini S, Gray K, Grelle S, Griffin SM, Grigoryan L, Grigoryan A, Grigoryev D, Gruber J, Guilaran J, Hadar B, Hahnel UJJ, Halperin E, Harvey AJ, Haugestad CAP, Herman AM, Hershfield HE, Himichi T, Hine DW, Hofmann W, Howe L, Huaman-Chulluncuy ET, Huang G, Ishii T, Ito A, Jia F, Jost JT, Jovanović V, Jurgiel D, Kácha O, Kankaanpää R, Kantorowicz J, Kantorowicz-Reznichenko E, Mintz KK, Kaya I, Kaya O, Khachatryan N, Klas A, Klein C, Klöckner CA, Koppel L, Kosachenko AI, Kothe EJ, Krebs R, Krosch AR, Krouwel APM, Kyrychenko Y, Lagomarsino M, Cunningham JL, Lees J, Leung TY, Levy N, Lockwood PL, Longoni C, Ortega AL, Loschelder DD, Lu JG, Luo Y, Luomba J, Lutz AE, Majer JM, Markowitz E, Marsh AA, Mascarenhas KL, Mbilingi B, Mbungu W, McHugh C, Meijers MHC, Mercier H, Mhagama FL, Michalaki K, Mikus N, Milliron SG, Mitkidis P, Monge-Rodríguez FS, Mora YL, Morais MJ, Moreau D, Motoki K, Moyano M, Mus M, Navajas J, Nguyen TL, Nguyen DM, Nguyen T, Niemi L, Nijssen SRR, Nilsonne G, Nitschke JP, Nockur L, Okura R, Öner S, Özdoğru AA, Palumbo H, Panagopoulos C, Panasiti MS, Pärnamets P, Paruzel-Czachura M, Pavlov YG, Payán-Gómez C, Pearson AR, da Costa LP, Petrowsky HM, Pfattheicher S, Pham NT, Ponizovskiy V, Pretus C, Rêgo GG, Reimann R, Rhoads SA, Riano-Moreno J, Richter I, Röer JP, Rosa-Sullivan J, Ross RM, Sabherwal A, Saito T, Sarrasin O, Say N, Schmid K, Schmitt MT, Schoenegger P, Scholz C, Schug MG, Schulreich S, Shreedhar G, Shuman E, Sivan S, Sjåstad H, Soliman M, Soud K, Spampatti T, Sparkman G, Spasovski O, Stanley SK, Stern JA, Strahm N, Suko Y, Sul S, Syropoulos S, Taylor NC, Tedaldi E, Tinghög G, Huynh LDT, Travaglino GA, Tsakiris M, Tüter İ, Tyrala M, Uluğ ÖM, Urbanek A, Valko D, van der Linden S, van Schie K, van Stekelenburg A, Vanags E, Västfjäll D, Vesely S, Vintr J, Vranka M, Wanguche PO, Willer R, Wojcik AD, Xu R, Yadav A, Zawisza M, Zhao X, Zhao J, Żuk D, and Van Bavel JJ
- Subjects
- Humans, Surveys and Questionnaires, Climate Change
- Abstract
Climate change is currently one of humanity's greatest threats. To help scholars understand the psychology of climate change, we conducted an online quasi-experimental survey on 59,508 participants from 63 countries (collected between July 2022 and July 2023). In a between-subjects design, we tested 11 interventions designed to promote climate change mitigation across four outcomes: climate change belief, support for climate policies, willingness to share information on social media, and performance on an effortful pro-environmental behavioural task. Participants also reported their demographic information (e.g., age, gender) and several other independent variables (e.g., political orientation, perceptions about the scientific consensus). In the no-intervention control group, we also measured important additional variables, such as environmentalist identity and trust in climate science. We report the collaboration procedure, study design, raw and cleaned data, all survey materials, relevant analysis scripts, and data visualisations. This dataset can be used to further the understanding of psychological, demographic, and national-level factors related to individual-level climate action and how these differ across countries., (© 2024. The Author(s).)
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- 2024
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35. Assessment of transcranial Doppler indices after MgSO 4 administration in severe preeclamptic women with neurologic symptoms.
- Author
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Lee S, Lee HJ, Yu EH, Yoon HJ, Jo HB, and Kim SC
- Subjects
- Humans, Female, Pregnancy, Adult, Young Adult, Blood Flow Velocity drug effects, Pre-Eclampsia physiopathology, Pre-Eclampsia drug therapy, Magnesium Sulfate administration & dosage, Ultrasonography, Doppler, Transcranial, Ophthalmic Artery diagnostic imaging, Cerebrovascular Circulation drug effects
- Abstract
Purpose: To investigate the effect of intravenous MgSO
4 on maternal cerebral hemodynamics as well as the association between altered Doppler indices of the ophthalmic arteries and ocular lesions in patients with preeclampsia., Methods: After each of the 15 included patients was diagnosed with preeclampsia, MgSO4 was infused followed by transcranial Doppler tests of the indices of the ophthalmic, anterior, middle, posterior cerebral, vertebral, and basilar arteries, followed by a second MgSO4 infusion. The peak, mean, diastolic velocity, and pulsatile and resistance indices of each artery were automatically measured during testing. Based on the emergent data, the cerebral perfusion pressure, resistance-area product, and cerebral flow index were calculated., Results: The cerebral perfusion pressure of the posterior cerebral arteries significantly decreased following the infusion of MgSO4 (p < 0.05). Before the infusion of MgSO4 , cerebral perfusion pressure and cerebral flow index of the ophthalmic arteries were significantly increased (p < 0.05) in the preeclamptic pregnant patients with ocular lesions compared those without ocular lesions. After the infusion of MgSO4 , the cerebral perfusion pressure and cerebral flow index of both ophthalmic arteries were slightly decreased, but the difference was not significant., Conclusions: Altered Doppler indices following the infusion of MgSO4 suggest significant changes in the hemodynamics of the posterior cerebral and ophthalmic arteries that are particularly related to the neurological signs and symptoms of women with preeclampsia. These findings may improve the understanding of the mechanism of the cerebral complications of preeclampsia. Advancing comprehension of these underlying mechanisms is postulated to play a pivotal role in the mitigation of hypertensive encephalopathy associated with preeclampsia., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2024
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36. Addressing climate change with behavioral science: A global intervention tournament in 63 countries.
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Vlasceanu M, Doell KC, Bak-Coleman JB, Todorova B, Berkebile-Weinberg MM, Grayson SJ, Patel Y, Goldwert D, Pei Y, Chakroff A, Pronizius E, van den Broek KL, Vlasceanu D, Constantino S, Morais MJ, Schumann P, Rathje S, Fang K, Aglioti SM, Alfano M, Alvarado-Yepez AJ, Andersen A, Anseel F, Apps MAJ, Asadli C, Awuor FJ, Azevedo F, Basaglia P, Bélanger JJ, Berger S, Bertin P, Białek M, Bialobrzeska O, Blaya-Burgo M, Bleize DNM, Bø S, Boecker L, Boggio PS, Borau S, Bos B, Bouguettaya A, Brauer M, Brick C, Brik T, Briker R, Brosch T, Buchel O, Buonauro D, Butalia R, Carvacho H, Chamberlain SAE, Chan HY, Chow D, Chung D, Cian L, Cohen-Eick N, Contreras-Huerta LS, Contu D, Cristea V, Cutler J, D'Ottone S, De Keersmaecker J, Delcourt S, Delouvée S, Diel K, Douglas BD, Drupp MA, Dubey S, Ekmanis J, Elbaek CT, Elsherif M, Engelhard IM, Escher YA, Etienne TW, Farage L, Farias AR, Feuerriegel S, Findor A, Freira L, Friese M, Gains NP, Gallyamova A, Geiger SJ, Genschow O, Gjoneska B, Gkinopoulos T, Goldberg B, Goldenberg A, Gradidge S, Grassini S, Gray K, Grelle S, Griffin SM, Grigoryan L, Grigoryan A, Grigoryev D, Gruber J, Guilaran J, Hadar B, Hahnel UJJ, Halperin E, Harvey AJ, Haugestad CAP, Herman AM, Hershfield HE, Himichi T, Hine DW, Hofmann W, Howe L, Huaman-Chulluncuy ET, Huang G, Ishii T, Ito A, Jia F, Jost JT, Jovanović V, Jurgiel D, Kácha O, Kankaanpää R, Kantorowicz J, Kantorowicz-Reznichenko E, Kaplan Mintz K, Kaya I, Kaya O, Khachatryan N, Klas A, Klein C, Klöckner CA, Koppel L, Kosachenko AI, Kothe EJ, Krebs R, Krosch AR, Krouwel APM, Kyrychenko Y, Lagomarsino M, Lamm C, Lange F, Lee Cunningham J, Lees J, Leung TY, Levy N, Lockwood PL, Longoni C, López Ortega A, Loschelder DD, Lu JG, Luo Y, Luomba J, Lutz AE, Majer JM, Markowitz E, Marsh AA, Mascarenhas KL, Mbilingi B, Mbungu W, McHugh C, Meijers MHC, Mercier H, Mhagama FL, Michalakis K, Mikus N, Milliron S, Mitkidis P, Monge-Rodríguez FS, Mora YL, Moreau D, Motoki K, Moyano M, Mus M, Navajas J, Nguyen TL, Nguyen DM, Nguyen T, Niemi L, Nijssen SRR, Nilsonne G, Nitschke JP, Nockur L, Okura R, Öner S, Özdoğru AA, Palumbo H, Panagopoulos C, Panasiti MS, Pärnamets P, Paruzel-Czachura M, Pavlov YG, Payán-Gómez C, Pearson AR, Pereira da Costa L, Petrowsky HM, Pfattheicher S, Pham NT, Ponizovskiy V, Pretus C, Rêgo GG, Reimann R, Rhoads SA, Riano-Moreno J, Richter I, Röer JP, Rosa-Sullivan J, Ross RM, Sabherwal A, Saito T, Sarrasin O, Say N, Schmid K, Schmitt MT, Schoenegger P, Scholz C, Schug MG, Schulreich S, Shreedhar G, Shuman E, Sivan S, Sjåstad H, Soliman M, Soud K, Spampatti T, Sparkman G, Spasovski O, Stanley SK, Stern JA, Strahm N, Suko Y, Sul S, Syropoulos S, Taylor NC, Tedaldi E, Tinghög G, Huynh LDT, Travaglino GA, Tsakiris M, Tüter İ, Tyrala M, Uluğ ÖM, Urbanek A, Valko D, van der Linden S, van Schie K, van Stekelenburg A, Vanags E, Västfjäll D, Vesely S, Vintr J, Vranka M, Wanguche PO, Willer R, Wojcik AD, Xu R, Yadav A, Zawisza M, Zhao X, Zhao J, Żuk D, and Van Bavel JJ
- Subjects
- Humans, Intention, Policy, Climate Change, Behavioral Sciences
- Abstract
Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.
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- 2024
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37. CT-001, a novel fast-clearing factor VIIa, enhanced the hemostatic activity in postpartum samples.
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Sim DS, Mallari CR, Hermiston TW, Bae D, Lee S, Allen T, Gilner J, Kim SC, and James AH
- Subjects
- Female, Humans, Pregnancy, Blood Coagulation Factors, Factor VIIa pharmacology, Postpartum Period, Thrombin, Tomography, X-Ray Computed, Hemostatics pharmacology, Postpartum Hemorrhage
- Abstract
Abstract: The hemostatic system is upregulated to protect pregnant mothers from hemorrhage during childbirth. Studies of the details just before and after delivery, however, are lacking. Recombinant factor VIIa (rFVIIa) has recently been granted approval by the European Medicines Agency for the treatment of postpartum hemorrhage (PPH). A next-generation molecule, CT-001, is being developed as a potentially safer and more efficacious rFVIIa-based therapy. We sought to evaluate the peripartum hemostatic status of pregnant women and assess the ex vivo hemostatic activity of rFVIIa and CT-001 in peripartum blood samples. Pregnant women from 2 study sites were enrolled in this prospective observational study. Baseline blood samples were collected up to 3 days before delivery. Postdelivery samples were collected 45 (±15) minutes after delivery. Between the 2 time points, soluble fibrin monomer and D-dimer increased whereas tissue factor, FVIII, FV, and fibrinogen decreased. Interestingly, the postdelivery lag time and time to peak in the thrombin generation assay were shortened, and the peak thrombin generation capacity was maintained despite the reduced levels of coagulation proteins after delivery. Furthermore, both rFVIIa and CT-001 were effective in enhancing clotting activity of postdelivery samples in activated partial thromboplastin time, prothrombin time, thrombin generation, and viscoelastic hemostatic assays, with CT-001 demonstrating greater activity. In conclusion, despite apparent ongoing consumption of coagulation factors at the time of delivery, thrombin output was maintained. Both rFVIIa and CT-001 enhanced the upregulated hemostatic activity in postdelivery samples, and consistent with previous studies comparing CT-001 and rFVIIa in vitro and in in vivo, CT-001 demonstrated greater activity than rFVIIa., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
- Published
- 2024
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38. Direct identification of interfacial degradation in blue OLEDs using nanoscale chemical depth profiling.
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Trindade GF, Sul S, Kim J, Havelund R, Eyres A, Park S, Shin Y, Bae HJ, Sung YM, Matjacic L, Jung Y, Won J, Jeon WS, Choi H, Lee HS, Lee JC, Kim JH, and Gilmore IS
- Abstract
Understanding the degradation mechanism of organic light-emitting diodes (OLED) is essential to improve device performance and stability. OLED failure, if not process-related, arises mostly from chemical instability. However, the challenges of sampling from nanoscale organic layers and interfaces with enough analytical information has hampered identification of degradation products and mechanisms. Here, we present a high-resolution diagnostic method of OLED degradation using an Orbitrap mass spectrometer equipped with a gas cluster ion beam to gently desorb nanometre levels of materials, providing unambiguous molecular information with 7-nm depth resolution. We chemically depth profile and analyse blue phosphorescent and thermally-activated delayed fluorescent (TADF) OLED devices at different degradation levels. For OLED devices with short operational lifetimes, dominant chemical degradation mainly relate to oxygen loss of molecules that occur at the interface between emission and electron transport layers (EML/ETL) where exciton distribution is maximised, confirmed by emission zone measurements. We also show approximately one order of magnitude increase in lifetime of devices with slightly modified host materials, which present minimal EML/ETL interfacial degradation and show the method can provide insight for future material and device architecture development., (© 2023. The Author(s).)
- Published
- 2023
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39. Corticolimbic structural connectivity encapsulates real-world emotional reactivity and happiness.
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Kim M, Shin S, Jyung M, Choi JA, Choi I, Kim MJ, and Sul S
- Subjects
- Female, Young Adult, Humans, Emotions, Diffusion Magnetic Resonance Imaging, Neuroimaging, Happiness, White Matter
- Abstract
Emotional reactivity to everyday events predicts happiness, but the neural circuits underlying this relationship remain incompletely understood. Here, we combined experience sampling methods and diffusion magnetic resonance imaging to examine the association among corticolimbic structural connectivity, real-world emotional reactivity and daily experiences of happiness from 79 young adults (35 females). Participants recorded momentary assessments of emotional and happiness experiences five times a day for a week, approximately 2 weeks after brain scanning. Model-based emotional reactivity scores, which index the degree to which moment-to-moment affective state varies with the occurrence of positive or negative events, were computed. Results showed that stronger microstructural integrity of the uncinate fasciculus and the external capsule was associated with both greater positive and negative emotional reactivity scores. The relationship between these fiber tracts and experienced happiness was explained by emotional reactivity. Importantly, this indirect effect was observed for emotional reactivity to positive but not negative real-world events. Our findings suggest that the corticolimbic circuits supporting socioemotional functions are associated with emotional reactivity and happiness in the real world., (© The Author(s) 2023. Published by Oxford University Press.)
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- 2023
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40. Perceived financial well-being and its association with frontostriatal functional connectivity, real-life anticipatory experiences, and everyday happiness.
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Shin WG, Jyung M, Choi I, and Sul S
- Subjects
- Humans, Prefrontal Cortex physiology, Nucleus Accumbens diagnostic imaging, Life Change Events, Happiness, Magnetic Resonance Imaging
- Abstract
Perceived financial well-being (FWB) is an important aspect of life that can affect one's attitude toward future experiences and happiness. However, the relationship between FWB, anticipatory experiences, and happiness, and the brain's functional architecture underlying this relationship remain unknown. Here, we combined an experience sampling method, multilevel modeling, and functional neuroimaging to identify the neural correlates of FWB and their associations with real-world anticipatory experiences and everyday happiness. Behaviorally, we found that individuals with greater FWB felt more positive and more interested when they expected positive events to occur, which in turn resulted in increased everyday happiness. Furthermore, the level of FWB was significantly associated with the strength of functional connectivity (FC) between the nucleus accumbens (NAc) and ventromedial prefrontal cortex (vmPFC) and the local coherence within the vmPFC. The frontostriatal FC and local coherence within the vmPFC were further predictive of everyday happiness via the anticipatory response involving interestedness during positive expectations. Our findings suggest that individual differences in FWB could be reflected in the functional architecture of brain's reward system that may contribute to shaping positive anticipatory experiences and happiness in daily life., (© 2023. The Author(s).)
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- 2023
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41. Effect of trifluoroacetic acid on InP/ZnSe/ZnS quantum dots: mimicking the surface trap and their effects on the photophysical properties.
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Sung YM, Kim TG, Yun DJ, Chae BG, Park H, Lee HS, Kim JH, Jun S, and Sul S
- Abstract
Understanding the precise effects of defects on the photophysical properties of quantum dots (QDs) is essential to their development with near-unity luminescence. Because of the complicated nature of defects in QDs, the origins and detailed roles of the defects still remain rarely understood. In this regard, we used detailed chemical analysis to investigate the effect of surface defects on the optical properties of InP/ZnSe/ZnS QDs by introducing shell defects through controlled trifluoroacetic acid (TFA) etching. TFA treatment on the InP/ZnSe/ZnS QDs partially removed the ZnS shell as well as ligands and reduced the quantum yield by generating energetically deep surface traps. The surface defects of QDs by TFA cause charged trap sites inducing an Auger recombination process with a rate of ca. 200 ps. Based on these results, we proposed possible trap-assisted non-radiative decay pathways between the band-edge state and surface deep traps in InP/ZnSe/ZnS QDs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2023
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42. Individual differences in gaze-cuing effect are associated with facial emotion recognition and social conformity.
- Author
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Shin WG, Park H, Kim SP, and Sul S
- Abstract
Spontaneous gaze following and the concomitant joint attention enable us to share representations of the world with others, which forms a foundation of a broad range of social cognitive processes. Although this form of social orienting has long been suggested as a critical starting point for the development of social and communicative behavior, there is limited evidence directly linking it to higher-level social cognitive processes among healthy adults. Here, using a gaze-cuing paradigm, we examined whether individual differences in gaze following tendency predict higher-order social cognition and behavior among healthy adults. We found that individuals who showed greater gaze-cuing effect performed better in recognizing others' emotion and had greater tendency to conform with group opinion. These findings provide empirical evidence supporting the fundamental role of low-level socio-attentional processes in human sociality., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Shin, Park, Kim and Sul.)
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- 2023
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43. Effect of the Presence of Silicone Oil in the Anterior Chamber After Complicated Retinal Detachment Surgery on Corneal Morphology by In Vivo Confocal Microscopy.
- Author
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Kasikci M, Sul S, Simsek HC, Karalezli A, Simsek M, and Korkmaz S
- Subjects
- Humans, Vitrectomy, Cornea surgery, Endothelium, Corneal, Anterior Chamber diagnostic imaging, Silicones pharmacology, Cell Count, Microscopy, Confocal, Silicone Oils pharmacology, Retinal Detachment diagnosis, Retinal Detachment surgery
- Abstract
Purpose: This study evaluated the corneal endothelium, stromal keratocytes, subbasal nerve number and density in patients with silicone oil transferred to the anterior camera after pseudophakic complicated retinal detachment surgery by in vivo laser scanning confocal microscopy (IVLSCM)., Methods: Sequential measurements were made by IVLSCM between 3-6 months after surgery in two groups of patients: a) with silicon oil migration (Group 1) and without silicone oil migration (Group 2)., Results: A total of 63 cases (Group 1: 32 and Group 2: 31) were examined. The mean ages of patients were 65 ± 12 and 61 ± 11 and M/F ratio was 18/14 and 17/14, respectively. Mean intraocular pressures were 16.60 ± 4.60 and 15.75 ± 5.70 mm Hg, respectively. Changes were detected by IVLSCM mostly on the superior part of the cornea. A significant decrease in endothelial cell density and the number was detected in group 1 (2072 ± 116.2 cells/mm
2 vs 2752 ± 512.3 cells/mm2 ; p < 0.001). Significant increases in posterior keratocyte density and stromal hyperreflective deposits were observed in group 1 (887 ± 45.8 cells/mm2 vs 725 ± 65.8 cells/mm2 ; p < 0.001). A significant negative correlation was observed between the size of stromal deposits and endothelial cell density ( r =-0.758; p < 0.001). The number and density of corneal subbasal nerves were significantly lower in group 1 (1.8 ± 0.8 and 4.8 ± 1.2 vs 420 ± 101 and 701 ± 112 µm/square; p < 0.001)., Conclusion: IVLSCM is a useful tool for the early detection of corneal abnormalities caused by silicone oil injection. This study verified silicone oil's detrimental effect on the corneal endothelium and revealed stromal changes in the anterior chamber, which we believe can be also been associated with the presence of silicone oil.- Published
- 2023
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44. Environmental vulnerability evolution in the Brazilian Amazon.
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Fiedler NC, Jesus RMM, Moreira FZ, Ramalho AHC, Santos ARD, and Souza KB
- Subjects
- Humans, Brazil, Ecosystem, Conservation of Natural Resources, Artificial Intelligence, Environmental Monitoring
- Abstract
Decision making and environmental policies are mainly based on propensity level to impact in the area. The propensity level can be determined through artificial intelligence techniques included in geotechnological universe. Thus, this study aimed to determine the areas of greatest vulnerability to human activities, in Amazon biome, through MODIS images of Land use and land cover (LULC) from the 2001 and 2013. Remote sensing, Euclidean distance, Fuzzy logic, AHP method and analysis of net variations were applied to specialize the classes of vulnerability in the states belonging to the Amazon Biome. From the results, it can be seen that the class that most evolved in a positive net gain during the evaluated period was "very high" and the one that most reduced was "high", showing that there was a transition from "high" to "very high" risk areas. The states with the largest areas under "very high" risk class were Mato Grosso (101,100.10 km2) and Pará (81,010.30 km2). It is concluded that the application of remote sensing techniques allows the determination and assessment of the environmental vulnerability evolution. Mitigation measures urgently need to be implemented in the Amazon biome. The methodology can be extended to any other area of the planet.
- Published
- 2023
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45. Using Alprazolam before phacoemulsification cataract surgery reduces complications and duration of the surgery.
- Author
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Korkmaz S, Kaderli A, Kaderli ST, Sul S, and Karalezli A
- Subjects
- Humans, Alprazolam, Retrospective Studies, Postoperative Complications etiology, Phacoemulsification methods, Cataract etiology, Lens Capsule, Crystalline surgery, Lenses, Intraocular adverse effects
- Abstract
Purpose: To evaluate the effect of preoperative Alprazolam on complications of phacoemulsification cataract surgery, duration of surgery and early reoperation rate., Methods: Records of 1026 eyes of 1026 consecutive patients underwent phacoemulsification with topical and intracameral anesthesia between 2016 and 2020 years were retrospectively reviewed. Patients were divided into two groups, with or without using Alprazolam before surgery. Patients with planned first-time surgery for senile cataract and at least three months follow-up postoperatively were included. Those who had pseudoexfoliation, small pupil, zonular weakness, corneal and hearing problem as well as traumatic, brown, mature, hypermature, and posterior polar cataracts were excluded. Main outcome measures were duration of surgery, posterior capsule rupture, rapid posterior capsule opacification (PCO) formation requiring the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser and reoperation rate in early postoperative periods., Results: Alprazolam and control groups included 490 and 536 eyes, respectively. Mean surgical time was shorter in Alprazolam group (10.2 ± 3 versus 12.2 ± 4 min; < 0.001). Rate of posterior capsule rupture was higher in control group (4 versus 15 eyes; = 0.02). Four eyes (0.8%) in control group underwent unplanned secondary surgical procedures in early postoperative period (P = 0.126). Rate of rapid PCO formation was higher in control group (1 versus 9 eyes; = 0.027)., Conclusions: Using Alprazolam before phacoemulsification can lead to less posterior capsule rupture, short operation time and prevent repetitive surgery. It also reduces rapid PCO formation and, thus, early Nd:YAG laser intervention due to better cleaning the posterior capsule during surgery. We conclude that Alprazolam not only reduces intraoperative complications, but also facilitates their management., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)
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- 2023
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46. Pt cocatalyst morphology on semiconductor nanorod photocatalysts enhances charge trapping and water reduction.
- Author
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Park B, Park WW, Choi JY, Choi W, Sung YM, Sul S, Kwon OH, and Song H
- Abstract
In photocatalysis, metal-semiconductor hybrid structures have been proposed for ideal photocatalytic systems. In this study, we investigate the effect of morphology and surface nature of Pt cocatalysts on photocatalytic hydrogen evolution activity in Pt-tipped CdSe nanorods. Three distinct morphologies of Pt cocatalysts were synthesized and employed as visible light photocatalysts. The rough tips exhibit the highest activity, followed by the round and cubic tips. Kinetic investigations using transient absorption spectroscopy reveal that the cubic tips exhibit lower charge-separated states feasible for reacting with water and water reduction rates due to their defectless surface facets. In contrast, the rough tips show a similar charge-separation value but a two-fold higher surface reaction rate than the round tips, resulting in a significant enhancement of hydrogen evolution. These findings highlight the importance of rational design on metal cocatalysts in addition to the main semiconductor bodies for maximizing photocatalytic activities., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2023
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47. Comparison of changes in number of hyperreflective dots after intravitreal ranibizumab or dexamethasone implant in patients with branch retinal vein occlusion.
- Author
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Karalezli A, Kaderli ST, Kaderli A, Kaya C, and Sul S
- Abstract
Purpose: To compare the effect of intravitreal ranibizumab (IVR) or intravitreal dexamethasone implants (IVD) on the regression of hyperreflective dots (HRDs) in patients with branch retinal vein occlusion (BRVO)., Materials and Methods: Thirty-seven eyes with cystoid macular edema who received IVR or IVD and followed up for at least 12 months were included in this study. The patients were divided into three Groups according to intravitreal treatments. Group 1 consisted of 12 eyes who received only IVD, Group 2 consisted of 10 eyes who received only IVR, and Group 3 consisted of 15 eyes who received both IVD and IVR. The number of HRDs and best-corrected visual acuity (BCVA) were compared between the Groups through the follow-up time., Results: The mean number of HRDs in inner and outer retinal layers was significantly decreased in Group 1 and Group 3 (For Group 1; P < 0.001, P = 0.001, for Group 3; P < 0.001, P < 0.001). At the 1
st year, the number of HRDs in inner and outer retinal layers was significantly lower in Group 1 and Group 3 than Group 2 (All P < 0.05). The BCVA was higher in Group 3 than Group 2 at 1st year ( P = 0.048)., Conclusion: The HRDs should be considered inflammatory markers in the follow-up of CME in BRVO., Competing Interests: The authors declare that there are no conflicts of interests of this paper., (Copyright: © 2023 Taiwan J Ophthalmol.)- Published
- 2023
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48. Umbelliferone Ameliorates Memory Impairment and Enhances Hippocampal Synaptic Plasticity in Scopolamine-Induced Rat Model.
- Author
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Choi GY, Kim HB, Cho JM, Sreelatha I, Lee IS, Kweon HS, Sul S, Kim SA, Maeng S, and Park JH
- Subjects
- Rats, Male, Animals, Acetylcholinesterase metabolism, Rats, Sprague-Dawley, Memory Disorders chemically induced, Memory Disorders drug therapy, Memory Disorders metabolism, Neuronal Plasticity, Hippocampus metabolism, Scopolamine adverse effects, Scopolamine metabolism, Alzheimer Disease metabolism
- Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder, characterized by memory loss and cognitive decline. Among the suggested pathogenic mechanisms of AD, the cholinergic hypothesis proposes that AD symptoms are a result of reduced synthesis of acetylcholine (ACh). A non-selective antagonist of the muscarinic ACh receptor, scopolamine (SCOP) induced cognitive impairment in rodents. Umbelliferone (UMB) is a Apiaceae-family-derived 7-hydeoxycoumarin known for its antioxidant, anti-tumor, anticancer, anti-inflammatory, antibacterial, antimicrobial, and antidiabetic properties. However, the effects of UMB on the electrophysiological and ultrastructure morphological aspects of learning and memory are still not well-established. Thus, we investigated the effect of UMB treatment on cognitive behaviors and used organotypic hippocampal slice cultures for long-term potentiation (LTP) and the hippocampal synaptic ultrastructure. A hippocampal tissue analysis revealed that UMB attenuated a SCOP-induced blockade of field excitatory post-synaptic potential (fEPSP) activity and ameliorated the impairment of LTP by the NMDA and AMPA receptor antagonists. UMB also enhanced the hippocampal synaptic vesicle density on the synaptic ultrastructure. Furthermore, behavioral tests on male SD rats (7-8 weeks old) using the Y-maze test, passive avoidance test (PA), and Morris water maze test (MWM) showed that UMB recovered learning and memory deficits by SCOP. These cognitive improvements were in association with the enhanced expression of BDNF, TrkB, and the pCREB/CREB ratio and the suppression of acetylcholinesterase activity. The current findings indicate that UMB may be an effective neuroprotective reagent applicable for improving learning and memory against AD.
- Published
- 2023
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49. Microvascular changes in obese adults detected by Optical Coherence Tomography Angiography.
- Author
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Alacamli G, Kaderli ST, Edebali S, Alacamli OG, Sul S, Canbek TD, and Karalezli A
- Subjects
- Humans, Adult, Fluorescein Angiography methods, Prospective Studies, Overweight complications, Obesity complications, Tomography, Optical Coherence methods, Retinal Vessels diagnostic imaging
- Abstract
Aim: The aim of this prospective, controlled, non-randomized study was the comparison of the retinal microvascular parameters of obese and nonobese adults. Methods: 184 eyes of 92 subjects were separated to 3 groups. 68 eyes were in the normal weight group, with a body mass index between 18.5 and 24.5 kg/ m2, 60 eyes were in the overweight group, with a body mass index between 25-29.9 kg/ m2, and 56 eyes were in the obese group, with a body mass index ≥ 30 kg/ m2. All the volunteers were applied visual acuity, ocular motility testing, and slit lamp and mydriatic fundus examination. Optical Coherence Tomography Angiography (OCT-A) scanning was practiced with Optovue (Optovue, Inc; Fremont, CA) on a 6.00 x 6.00 mm macular region, in the central fovea. Results: 184 eyes of ninety-two patients were involved in this prospective study. The vessels' density (VD) in the optic nerve head (ONH) were significantly lower in the overweight and obese adult volunteers compared to the normal weight control group. However, other OCTA parameters (including macular VDs, Foveal avascular zone (FAZ), choriocapillaris plexus (CCP) area) did not demonstrate any significant difference between groups. Subfoveal choroidal thickness (SCT) was higher in the overweight and obese patients when compared to the normal weight control group. Central macular thickness (CMT) did not reveal any significant difference between groups. Conclusion: Even though clinicians are limited in pointing out any differential findings in obese patients only by fundus examination, OCT-A provides a predictable view of the microvascular changes in the retina and choroid in obese patients. Abbreviations: BMI = Body mass index, WHO = World Health Organization, AMD = Age-related macular degeneration, CT = Choroidal thickness, OCTA = Optical Coherence Tomography Angiography, (W/H) ratio = Waist-hip ratio, ETDRS = Early Treatment Diabetic Retinopathy Study, VD = Vessel density, SCP = Superficial capillary plexus, DCP = Deep capillary plexus, CCP = Flow area of the choriocapillaris, FAZ = Avascular zone, CMT = Central macular thickness, ONH = Optic nerve head., (#x00A9; The Authors.Romanian Society of Ophthalmology.)
- Published
- 2023
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50. On the relationship between the social brain, social connectedness, and wellbeing.
- Author
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Kim MJ and Sul S
- Abstract
The emergence of social neuroscience in the past two decades has offered a useful neurocognitive framework for understanding human social behavior. Of importance, social neuroscience research aimed to provide mechanistic explanations for the established link between wellbeing and social behavioral phenomena-particularly those reflective of social connectedness. Here, we provide an overview of the relevant literature focusing on recent work using functional magnetic resonance imaging (fMRI). In general, fMRI research demonstrated that aspects of social connectedness that are known to either positively (e.g., social acceptance) or negatively (e.g., social isolation) impact wellbeing also modulated the activity of subcortical reward system accordingly. Similar modulatory influence was found for the activity of other brain regions such as the medial prefrontal cortex, which are typically regarded as components of the "social brain" that support a wide range of functions related to social cognition and behavior. Elucidating such individual differences in brain activity may shed light onto the neural underpinnings of the link between social connectedness and wellbeing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kim and Sul.)
- Published
- 2023
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