4,846 results on '"Kim K."'
Search Results
2. The Sunburst Arc with JWST: I. Detection of Wolf-Rayet stars injecting nitrogen into a low-metallicity, z = 2.37 proto-globular cluster leaking ionizing photons.
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Emil Rivera-Thorsen, T., Chisholm, J., Welch, B., Rigby, J. R., Hutchison, T., Florian, M., Sharon, K., Choe, S., Dahle, H., Bayliss, M. B., Khullar, G., Gladders, M., Hayes, M., Adamo, A., Owens, M. R., and Kim, K.
- Abstract
We report the detection of a population of Wolf-Rayet (WR) stars in the Sunburst Arc, a strongly gravitationally lensed galaxy at redshift z = 2.37. As the brightest known lensed galaxy, the Sunburst Arc has become an important cosmic laboratory for studying star and cluster formation, Lyman α (Lyα) radiative transfer, and Lyman continuum (LyC) escape. Here, we present the first results of JWST/NIRSpec IFU observations of the Sunburst Arc, focusing on a stacked spectrum of the 12-fold imaged Sunburst LyC-emitting (LCE) cluster. In agreement with previous studies, we find that the Sunburst LCE cluster is a very massive, compact star cluster with M
dyn = (9 ± 1)×106 M⊙ . Our age estimate of 4.2–4.5 Myr is much larger than the crossing time of tcross = 183 ± 9 kyr, indicating that the cluster is dynamically evolved and consistent with it being gravitationally bound. We find a significant nitrogen enhancement of the low ionization state interstellar medium (ISM), with log(N/O) = − 0.74 ± 0.09, which is ≈0.8 dex above typical values for H II regions of a similar metallicity in the local Universe. We find broad stellar emission complexes around He IIλ4686 and C IVλ5808 with associated nitrogen emission; this is the first time WR signatures have been directly observed at redshifts above ∼0.5. The strength of the WR signatures cannot be reproduced by stellar population models that only include single-star evolution. While models with binary evolution better match the WR features, they still struggle to reproduce the nitrogen-enhanced WR features. JWST reveals the Sunburst LCE cluster to be a highly ionized proto-globular cluster with low oxygen abundance and extreme nitrogen enhancement that hosts a population of WR stars, likely including a previously suggested population of very massive stars (VMSs), which together are rapidly enriching the surrounding medium. [ABSTRACT FROM AUTHOR]- Published
- 2024
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3. The role of multimodality imaging in the selection and management of patients treated with cytoreductive surgery and HIPEC.
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John, V., Mercer, J., Kim, K., and Kochhar, R.
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Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is the mainstay of potentially curative surgical treatment for malignancies that have spread to peritoneal surfaces. This surgical procedure is however associated with high morbidity and appropriate patient selection and planning is therefore essential. Available multimodality imaging techniques include CT with oral and intravenous contrast, MRI including use of dedicated peritoneal protocol and FDG-PET/CT. These used with the correct technique, read by specialist radiologists and discussed under the auspices of a dedicated multidisciplinary team, can help to improve outcomes. We demonstrate that imaging not only provides information about peritoneal disease burden but more importantly want to shift the reader's focus to disease distribution. Our examples highlight how imaging helps avoid futile surgery by identifying patients with disease in unfavourable sites and show the strength and limitations of the various imaging modalities. We share how MR imaging can help identify multifocal and often occult sites including widespread miliary disease. Our examples provide a comprehensive overview demonstrating how imaging can help plan surgery by identifying patients who may need splenic vaccinations, counselling for stoma, egg harvesting and input from surgeons with other specialist expertise greatly increasing likelihood of achieving complete cytoreduction. [ABSTRACT FROM AUTHOR]
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- 2024
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4. The GRB221009A gamma-ray burst as revealed by the gamma-ray spectrometer onboard the KPLO (Danuri).
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Kim, K. J., Kim, S. Y., Paige, D., Grodner, J., Choi, Y., Park, J. H., Kim, Y. K., Park, K. S., Lee, K. B., Yamashita, N., Berezhnoy, A. A., and Wöhler, C.
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GAMMA ray bursts ,SPECTROMETERS ,BINS - Abstract
The strongest gamma-ray burst (GRB) of the century, GRB20221009A, has been detected by the Korean Pathfinder Lunar Orbiter Gamma-ray Spectrometer (KGRS) instrument onboard the Korean Pathfinder Lunar Orbiter (KPLO). KGRS uses a LaBr
3 detector to measure GRB counts with five energy bins in the energy range from 30 keV to 12 MeV. KGRS detected GRB221009A at a distance of 1.508 million kilometers from the Earth. The full duration of the main burst was recorded between 13:20 and 13:26 on October 9, 2022 with peak counts of over 1000 times background. The dead time of KGRS reached as high as 50%, and the intrinsic gamma-ray spectrum of LaBr3 was significantly altered. [ABSTRACT FROM AUTHOR]- Published
- 2024
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5. Inclusive quasielastic neutrino-nucleus scattering with energy density functional nuclear models.
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Kim, K. S., Choi, Soonchul, Gil, Hana, and Hyun, Chang Ho
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- 2024
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6. Neuronal ceroid lipofuscinosis in a Schapendoes dog is caused by a missense variant in CLN6.
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Bellamy, Kim K. L., Skedsmo, Fredrik S., Hultman, Josefin, Jansen, Johan Høgset, and Lingaas, Frode
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NEURONAL ceroid-lipofuscinosis ,MISSENSE mutation ,DOGS ,LYSOSOMAL storage diseases ,WHOLE genome sequencing ,CENTRAL nervous system ,DYSPLASIA - Abstract
Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative disorders that occur in humans, dogs, and several other species. NCL is characterised clinically by progressive deterioration of cognitive and motor function, epileptic seizures, and visual impairment. Most forms present early in life and eventually lead to premature death. Typical pathological changes include neuronal accumulation of autofluorescent, periodic acid‐Schiff‐ and Sudan black B‐positive lipopigments, as well as marked loss of neurons in the central nervous system. Here, we describe a 19‐month‐old Schapendoes dog, where clinical signs were indicative of lysosomal storage disease, which was corroborated by pathological findings consistent with NCL. Whole genome sequencing of the affected dog and both parents, followed by variant calling and visual inspection of known NCL genes, identified a missense variant in CLN6 (c.386T>C). The variant is located in a highly conserved region of the gene and predicted to be harmful, which supports a causal relationship. The identification of this novel CLN6 variant enables pre‐breeding DNA‐testing to prevent future cases of NCL6 in the Schapendoes breed, and presents a potential natural model for NCL6 in humans. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Effects of the Combined Odor Reducing Additive on Fecal Fermentation Characteristics and Growth Performance in Hanwoo Steers.
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Kim, K. H. and Park, B. K.
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LIVESTOCK productivity ,BACILLUS licheniformis ,AGRICULTURAL laborers ,CONTROL groups ,BACILLUS (Bacteria) ,ODORS - Abstract
Background: Odors from livestock facilities are mainly caused by livestock manure. This causes deterioration of the health of the farm workers and the productivity of livestock. Complex additives with different actions are required to effectively reduce fecal contaminants. This study was conducted to investigate the effects of combined odor reducing additive (CORA) supplementation on the odor emission of feces and the growth performance of Hanwoo steers. Methods: Ninety-six Hanwoo steers were randomly assigned to the following four groups: control group fed with CORAunsupplemented formula feed; T0.05 group fed with 0.05% CORA-supplemented formula feed; T0.1 group fed with 0.1% CORAsupplemented formula feed and T0.2 group fed with 0.2% CORA-supplemented formula feed. The CORA comprised 88% zeolite, 3% Bacillus licheniformis, 3% Bacillus polyfermenticus and 6% saponin. Result: The fecal NH
3 -N gas emission was significantly lower in the T0.2 group than in the control group (P<0.05). The fecal H2 S gas emission at 20 d of incubation was lower in the T0.2 group than in the control group (P<0.05). The fecal NH3 -N concentration was lower in proportion in all the groups with different supplementation levels of CORA than in the control group after 7 d of incubation (P<0.05). The number of fungi in feces was lower in the treatment groups than in the control group and the lowest was for T0.2 group (P<0.05). The results of this study indicated that CORA supplementation can reduce the emission of harmful gases (NH3 -N and H2 S) and odor-causing substances in feces and inhibit mold growth. [ABSTRACT FROM AUTHOR]- Published
- 2024
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8. Role of hidden-color components in the tetraquark mixing model.
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Kim, Hungchong and Kim, K. S.
- Abstract
Multiquarks can have two-hadron components and hidden-color components in their wave functions. The presence of two-hadron components in multiquarks introduces a potential source of confusion, particularly with respect to their resemblance to hadronic molecules. On the other hand, hidden-color components are essential for distinguishing between multiquarks and hadronic molecules. In this work, we study the hidden-color components in the wave functions of the tetraquark mixing model, a model that has been proposed as a suitable framework for describing the properties of two nonets in the J P = 0 + channel: the light nonet [ a 0 (980) , K 0 ∗ (700) , f 0 (500) , f 0 (980) ] and the heavy nonet [ a 0 (1450) , K 0 ∗ (1430) , f 0 (1370) , f 0 (1500) ]. Our analysis reveals a substantial presence of hidden-color components within the tetraquark wave functions. To elucidate the impact of hidden-color components on physical quantities, we conduct computations of the hyperfine masses, ⟨ V CS ⟩ , for the two nonets, considering scenarios involving only the two-meson components and those incorporating the hidden-color components. We demonstrate that the hidden-color components constitute an important part of the hyperfine masses, such that the mass difference formula, Δ M ≈ Δ ⟨ V CS ⟩ , which has been successful for the two nonets, cannot be achieved without the hidden-color contributions. This can provide another evidence supporting the tetraquark nature of the two nonets. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Enhancing Qualitative and Quantitative Data Linkages in Complex Mixed Methods Designs: Illustrations From a Multi-phase Healthcare Delivery Study.
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Chandanabhumma, P. Paul, Swaminathan, Sriram, Cabrera, Lourdes M., Hou, Hechuan, Yang, Guangyu, Kim, K. Dennie, Janda, Allison M., Nassar, Khalil, Malani, Preeti N., Zhang, Min, Funk, Russell J., Aaronson, Keith D., Wu, Justine P., Pagani, Francis D., and Likosky, Donald S.
- Abstract
While mixed methods research is increasingly used to examine determinants of unwarranted variability in healthcare delivery and outcomes, novel integrative approaches are required to meet the needs of mixed methods healthcare delivery research. This article describes novel refining strategies that enhance the linkage between qualitative and quantitative dimensions of a mixed methods healthcare delivery research study. Leveraging our study experiences, this paper demonstrates several refining strategies: (1) using mediated allocation concealment to facilitate qualitative sampling; (2) informing qualitative inquiry through quantitative analytics; and (3) training and immersing multidisciplinary researchers in qualitative data collection and analysis. Developing and implementing strategies in mixed methods healthcare delivery research could advance methodological rigor and strengthen multidisciplinary collaboration. [ABSTRACT FROM AUTHOR]
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- 2024
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10. WILDbase: towards a common database to improve wildlife disease surveillance in Europe.
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de Cock, Marieke P., Baede, Valérie O., Wijburg, Sara R., Burt, Sara A., van Tiel, Robert F. N. A., Wiskerke, Kim K., van der Post, Jens R. J., van der Poel, Wim H. M., Sprong, Hein, and Maas, Miriam
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- 2024
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11. Bisphosphonate treatment for skeletal complications in paediatric cancer--Experience from a single tertiary centre.
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Utriainen, Pauliina, Stenberg, Jalmari E. E., Vettenranta, Kim K., and Mäkitie, Outi M.
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STEM cell transplantation ,CHILDHOOD cancer ,CHILD patients ,VERTEBRAL fractures ,THERAPEUTIC complications ,VERTEBRAE injuries ,BONE density - Abstract
Aims: The aim was to analyse the use and safety of bisphosphonate treatment for metabolic bone complications in paediatric cancer patients. Methods: We retrospectively describe our experience with bisphosphonate treatment in 25 childhood cancer patients (aged <18 years) in a single tertiary hospital between 1999 and 2020. Results: The most common primary diagnosis was acute lymphoblastic leukaemia (n = 16) and Hodgkin lymphoma (n = 3). Eleven patients (44%) had received allogeneic stem cell transplantation and two patients autologous stem cell transplantation. Sixteen patients (64%) had been treated with radiotherapy, either total-body (n = 11) or local (n = 5). The main indication for bisphosphonates was osteoporosis with vertebral compression fractures in 13/25, osteonecrosis in 6/25 and hypercalcaemia in 2/25. The bisphosphonate treatment was started on average 13 (range 0-76) months after the diagnosis of the bone complication. Bisphosphonate treatment lasted between weeks (hypercalcaemia) to 5 years (severe osteoporosis). Mild, non-symptomatic hypophosphatemia (n = 8), hypocalcaemia (n = 6) and moderate, transient pain (n = 6) were the most common adverse effects. No severe side effects were observed even when bisphosphonates were administered concomitantly with chemotherapy. Bone mineral density significantly improved with the bisphosphonate treatment (mean lumbar spine Z-score -1.17 vs. -0.07, p < 0.001). Conclusion: Bisphosphonate treatment was well tolerated in this paediatric patient cohort. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Compassion Fatigue, Resilience, and Endurance of Special Educators in Rural P–12 and Higher Education.
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Floyd, Kim K., Horn, Annemarie, and Sherfinski, Melissa
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PSYCHOLOGICAL resilience ,RISK assessment ,EMPLOYEE retention ,QUALITY of work life ,PSYCHOLOGY of teachers ,PSYCHOLOGICAL burnout ,QUALITATIVE research ,SELF-efficacy ,INTERPROFESSIONAL relations ,RESPECT ,MENTAL health ,UNIVERSITIES & colleges ,CONTENT analysis ,WORK-life balance ,EMOTIONS ,MENTORING ,WAGES ,DESCRIPTIVE statistics ,SURVEYS ,THEMATIC analysis ,RURAL conditions ,COLLEGE teacher attitudes ,SPECIAL education ,SOCIAL support ,SECONDARY traumatic stress ,VOCATIONAL guidance - Abstract
The effects of mental health challenges in the United States are growing and affect both Grades P–12 special education teachers and faculty at institutions of higher education (IHE). Educators struggle with compassion fatigue and associated burnout. With educators leaving the field for a plethora of reasons, it is vital to examine factors that support those who remain in education. Thus, we analyzed factors that support the retention of educators at both levels of instruction. In a qualitative analysis of data from survey respondents (N = 200), we examined the resiliency and endurance of practicing rural P–12 special educators and faculty at IHEs. Results from inductive content analysis indicate that factors leading to persistence in education begin with educators finding meaning in their teaching. Educators who demonstrate career endurance have a strong sense of self-efficacy in their teaching abilities, receive emotional benefits from their students, and have quality opportunities to mentor and collaborate with others. By contrast, some educators indicate burnout is a key factor for leaving the field, and reported reasons include low pay, paperwork, poor work/life balance, lack of respect, and the mental health of themselves and their students. Based on these findings, we offer recommendations for research and practice. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Editorial: Fetal analgesia: a conundrum for the physiologist, a tenet for the surgeon.
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Bellieni, Carlo V., Doheny, Kim K., Munoz, Maria A. Flores, and Pelizzo, Gloria
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SERIAL publications ,ANALGESIA ,ALLIED health personnel ,PAIN ,FETAL surgery ,ANESTHESIA - Abstract
This document is an editorial titled "Fetal analgesia: a conundrum for the physiologist, a tenet for the surgeon." It discusses the topic of fetal pain and the challenges surrounding its understanding and treatment. The authors highlight the evidence of fetal pain and the need for further research to determine the exact gestational age at which fetal pain is a real phenomenon. They also acknowledge the mysteries surrounding the type of pain that the fetus perceives and how it is experienced. The editorial calls for researchers to continue their efforts to shed light on these mysteries and advance our understanding of fetal pain. [Extracted from the article]
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- 2024
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14. First-principles evaluation of dopant impact on structural deformability and processability of Li7La3Zr2O12.
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Dive, A., Kim, K., Kang, S., Wan, L. F., and Wood, B. C.
- Abstract
Li
7 La3 Zr2 O12 (LLZO) and related ceramic solid electrolytes feature excellent stability and reasonable ionic conductivity, but processing remains challenging. High-temperature co-sintering is required for successful integration with the electrode, which is energetically costly and can lead to unacceptable cathode degradation. The introduction of dopants can promote lower-temperature processing by improving deformability and disrupting lattice integrity; however, an unbiased, systematic study correlating these properties to the dopant chemistry and composition is lacking. Here, we rely on a set of static and dynamic metrics derived from first-principles simulations to estimate the impact of doping on LLZO processability by quantifying LLZO structural deformability. We considered three distinct dopants (Al, Ba, and Ta) as representatives of substitutional incorporation on Li, La, and Zr sites. Our descriptors indicate that doping in general positively impacts lattice deformability, although significant sensitivities to dopant identity and concentration are observed. Amongst the tested dopants, Al doping (on the Li site) appears to have the greatest impact, as signaled across nearly the entire set of computed features. We suggest that these proxy descriptors, once properly calibrated against well-controlled experiments, could enable the use of first-principles simulations to computationally screen new ceramic electrolyte compositions with improved processability. [ABSTRACT FROM AUTHOR]- Published
- 2024
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15. Nonproportionality of NaI(Tl) scintillation detector for dark matter search experiments.
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Lee, S. M., Adhikari, G., Carlin, N., Cho, J. Y., Choi, J. J., Choi, S., Ezeribe, A. C., França, L. E., Ha, C., Hahn, I. S., Hollick, S. J., Jeon, E. J., Joo, H. W., Kang, W. G., Kauer, M., Kim, B. H., Kim, H. J., Kim, J., Kim, K. W., and Kim, S. H.
- Abstract
We present a comprehensive study of the nonproportionality of NaI(Tl) scintillation detectors within the context of dark matter search experiments. Our investigation, which integrates COSINE-100 data with supplementary γ spectroscopy, measures light yields across diverse energy levels from full-energy γ peaks produced by the decays of various isotopes. These γ peaks of interest were produced by decays supported by both long and short-lived isotopes. Analyzing peaks from decays supported only by short-lived isotopes presented a unique challenge due to their limited statistics and overlapping energies, which was overcome by long-term data collection and a time-dependent analysis. A key achievement is the direct measurement of the 0.87 keV light yield, resulting from the cascade following electron capture decay of 22 Na from internal contamination. This measurement, previously accessible only indirectly, deepens our understanding of NaI(Tl) scintillator behavior in the region of interest for dark matter searches. This study holds substantial implications for background modeling and the interpretation of dark matter signals in NaI(Tl) experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Observation and Numerical Simulation of Cold Ions Energized by EMIC Waves.
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Kim, K.‐H., Jun, C.‐W., Kwon, J.‐W., Lee, J., Shiokawa, K., Miyoshi, Y., Kim, E.‐H., Min, K., Seough, J., Asamura, K., Shinohara, I., Matsuoka, A., Yokota, S., Kasahara, Y., Kasahara, S., Hori, T., Keika, K., Kumamoto, A., and Tsuchiya, F.
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COMPUTER simulation ,IONS ,LINEAR polarization ,NUMERICAL analysis ,WAVE analysis ,MAGNETIC fields - Abstract
This is the first report of significant energization (up to 7,000 eV) of low‐energy He+ ions, which occurred simultaneously with H‐band electromagnetic ion cyclotron (EMIC) wave activity, in a direction mostly perpendicular to the ambient magnetic field. The event was detected by the Arase satellite in the dayside plasmatrough region off the magnetic equator on 15 May 2019. The peak energy of the He+ flux enhancements is mostly above 1,000 eV. At some interval, the He+ ions are energized up to ∼7,000 eV. The H‐band waves are excited in a frequency band between the local crossover and helium gyrofrequencies and are close to a linear polarization state with weakly left‐handed or right‐handed polarization. The normal angle of the waves exhibits significant variation between 0° and 80°, indicating a non‐parallel propagation. We run a hybrid code with parameters estimated from the Arase observations to examine the He+ energization. The simulations show that cold He+ ions are energized up to more than 1,000 eV, similar to the spacecraft observations. From the analysis of the simulated wave fields and cold plasma motions, we found that the ratio of the wave frequency to He+ gyrofrequency is a primary factor for transverse energization of cold He+ ions. As a consequence of the numerical analysis, we suggest that the significant transverse energization of He+ ions observed by Arase is attributed to H‐band EMIC waves excited near the local helium gyrofrequency. Key Points: Strong H‐band EMIC waves were detected in the dayside plasmatrough region off the magnetic equator by the Arase spacecraftThe H‐band waves energize cold He+ ions to levels above ∼1,000 eV in the direction perpendicular to the background magnetic fieldSimulation indicates that the ratio of the wave frequency to He+ gyrofrequency is a primary factor in the strong energization of He+ ions [ABSTRACT FROM AUTHOR]
- Published
- 2024
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17. Analysis of the cause of noise when the drawbridge goes up and down through non‐destructive diagnosis.
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Kim, K. J. and Lee, J.‐W.
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NOISE ,NONDESTRUCTIVE testing ,DEFLECTION (Mechanics) ,TORSION ,DIAGNOSIS - Abstract
Copyright of Materialwissenschaft und Werkstoffechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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18. A Systematic Review of Psychospiritual Interventions in the NICU: Supporting Parents' Mental Health and Psychological Well-Being.
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Brelsford, Gina M., Doheny, Kim K., and Stoner, Jennifer
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- 2024
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19. Mothers' and Fathers' Coping and Psychological Outcomes Post Neonatal Intensive Care Unit (NICU) Discharge: The Role of Religious and Spiritual Coping.
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Brelsford, Gina M., Sastry, Aishwarya, and Doheny, Kim K.
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NEONATAL intensive care units ,FATHER-child relationship ,FATHERS ,ACUTE stress disorder ,PARENT-infant relationships ,CENTER for Epidemiologic Studies Depression Scale ,INFANTS ,MOTHERS ,ACADEMIC medical centers - Abstract
Research shows that parents of infants admitted to a neonatal intensive care unit (NICU) tend to experience significant levels of anxiety, stress, and depression. However, few studies have explored the difference between mothers' and fathers' use of religious and spiritual (R/S) coping and mental health after the family is discharged from the NICU. Participants were 131 mothers and 53 fathers (N = 184) who completed the COPE Inventory, the Brief RCOPE, the Penn State Worry Questionnaire, the Center for Epidemiologic Studies Depression Scale—Revised (CESD-R), and the Stanford Acute Stress Reaction Questionnaire. Participants were acquired from the Pennsylvania Bureau of Health Statistics and Studyfinder at a university medical center. Mothers were contacted via regular mail with a survey for the mother and her co-parent/significant other to complete separately. Babies were born on average at 31.65 weeks' gestation and spent on average 35.10 days in the NICU. Mothers' mean scores on depression, anxiety, and stress were significantly higher than fathers' scores. Further, use of negative R/S coping was a salient predictor of depression for fathers even after accounting for secular coping. For mothers, negative R/S coping was related to greater anxiety and stress, while use of positive R/S was linked to lower levels of anxiety after accounting for secular forms of coping. Thus, mothers and fathers may experience stress, anxiety, and depression at different levels following NICU discharge. Their ways of coping with the new reality of having a recently discharged infant can also vary, with important mental health implications. The use of negative R/S coping may have detrimental impacts on these parents' mental health and family functioning. A family-centered approach that includes psychospiritual dimensions is warranted for better parental outcomes post NICU discharge. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Radionuclides deposition on sea surface following hypothetical accidental releases at Korean nuclear power plant.
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Kim, K. O., Kovalets, I. V., Jung, K. T., and Bezhenar, R. V.
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RADIOISOTOPES ,ATMOSPHERIC models ,ATMOSPHERIC transport ,TYPHOONS ,ATMOSPHERIC deposition ,SPRING ,PARTICLE size determination ,NUCLEAR power plants ,NUCLEAR reactors - Abstract
The scenarios of deposition on the sea surface around the Korean Peninsula following hypothetical release at Kori NPP were studied by application of the atmospheric transport model FLEXPART. The series of 1460 dispersion scenarios was calculated, covering the time period of 1 year. The total depositions on the surfaces of the East/Japan Sea (EJS), Yellow Sea (YS), East China Sea (ECS), and near-coast zone of 200-km vicinity around the Korean Peninsula, normalized on the total emission inventory were analyzed. The normalized deposition on the total area of 3 seas varied by more than 2 orders of magnitude from 0.003 to 0.59. The fraction of wet deposition in total deposition varied from 0 to 0.99. The selected most heavy deposition scenarios were divided into those dominated by dry deposition and wet deposition. The most conservative release scenarios (7 August 2020 and 2 September 2020) were dominated by wet deposition and were caused by the monsoon rainband and passage of the typhoon. In the scenario of 7 August 2020, 96% of deposition appeared in the near-coast zone. Cluster analysis of dispersion scenarios confirmed strong seasonal dependence of deposition patterns. For EJS and YS, the maximum average deposition was reached in the 'Summer' cluster. For ECS the maximum average normalized deposition was reached in the 'Spring + Fall' cluster ( D r = 0.055 ). Minimum average deposition on all seas was obtained for the 'Winter' cluster. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. 3-CARENE SUPPRESSES INFLAMMATORY CYTOKINE INTERLEUKIN-4, INTERLEUKIN-5 AND INTERLEUKIN-13 IN AMURINE MODEL OF ASTHMA.
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KIM, K., KIM, Y., LEE, J., LEE, M., AHN, C., PARK, M.-J., NA, H., and JEUNG, E.-B.
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Asthma is a common airway disease associated with allergic inflammation. Environmental factors, such as pollens, pollution, insect-borne antigens, or commercial chemicals, cause this disease. The common symptoms of this airway allergic reaction are increasing mucus, narrowing of the airway wall, coughing, and chest tightness. Medications, such as steroids, alleviate the disease but with severe side effects. Several studies have reported the anti-inflammatory effects of tree-based essential oil components, particularly 3-carene. Therefore, this study used 3-carene to determine if it alleviates asthmatic symptoms in the murine model. First, BALB/c mice were sensitized to an ovalbumin and aluminum hydroxide mixture on day 7th and 14th. From days 21st to 23rd, the mice were challenged with 3-carene and budesonide. The lung trachea, plasma, and bronchiolar lavage fluid (BAL fluid) were collected on day 24. The 3-carene treatment suppressed the cytokine gene expression, such as interleukin-4 (IL-4), IL-5, and IL-13, reducing the lung epithelial cell thickness in the asthmatic model. These results suggest that essential oil 3-carene has an anti-asthmatic effect. [ABSTRACT FROM AUTHOR]
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- 2024
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22. In a novel autoimmune and high-pressure glaucoma model a complex immune response is induced.
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Reinehr, Sabrina, Wulf, Julien, Theile, Janine, Schulte, Kim K., Peters, Marcus, Fuchshofer, Rudolf, Dick, H. Burkhard, and Joachim, Stephanie C.
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IMMUNE complexes ,IMMUNE response ,RETINAL ganglion cells ,TUMOR necrosis factors ,GLAUCOMA - Abstract
Background: The neurodegenerative processes leading to glaucoma are complex. In addition to elevated intraocular pressure (IOP), an involvement of immunological mechanisms is most likely. In the new multifactorial glaucoma model, a combination of high IOP and optic nerve antigen (ONA) immunization leads to an enhanced loss of retinal ganglion cells accompanied by a higher number of microglia/macrophages in the inner retina. Here, we aimed to evaluate the immune response in this new model, especially the complement activation and the number of T-cells, for the first time. Further, the microglia/macrophage response was examined in more detail. Methods: Six-week-old wildtype (WT+ONA) and bB1-connective tissue growth factor high-pressure mice (CTGF+ONA) were immunized with 1 mg ONA. A wildtype control (WT) and a CTGF group (CTGF) received NaCl instead. Six weeks after immunization, retinae from all four groups were processed for immunohistology, RT-qPCR, and flow cytometry, while serum was used for microarray analyses. Results: We noticed elevated numbers of C1q+ cells (classical complement pathway) in CTGF and CTGF+ONA retinae as well as an upregulation of C1qa, C1qb, and C1qc mRNA levels in these groups. While the complement C3 was only increased in CTGF and CTGF+ONA retinae, enhanced numbers of the terminal membrane attack complex were noted in all three glaucoma groups. Flow cytometry and RT-qPCR analyses revealed an enhancement of different microglia/macrophages markers, including CD11b, especially in CTGF and CTGF+ONA retinae. Interestingly, increased retinal mRNA as well as serum levels of the tumor necrosis factor a were found throughout the different glaucoma groups. Lastly, more T-cells could be observed in the ganglion cell layer of the new CTGF+ONA model. Conclusion: These results emphasize an involvement of the complement system, microglia/macrophages, and T-cells in glaucomatous disease. Moreover, in the new multifactorial glaucoma model, increased IOP in combination with autoimmune processes seem to enforce an additional T-cell response, leading to a more persistent pathology. Hence, this new model mimics the pathomechanisms occurring in human glaucoma more accurately and could therefore be a helpful tool to find new therapeutic approaches for patients in the future. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Improving the degradation and magnetization performance of FePC amorphous alloys by annealing treatment.
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Qi, Z. G., Chen, Q., Wang, Z. X., Song, Z. Q., Kim, K. B., Pang, J., Zhang, X. H., and Wang, W. M.
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AMORPHOUS alloys ,ELECTRIC batteries ,MAGNETIZATION ,RHODAMINE B ,MELT spinning ,GRAIN size - Abstract
The Fe
80 Px C20-x ingots and amorphous ribbons (4.5 ≤ x ≤ 6.5) are arc melted and melt spun respectively. The Rhodamine B degradation performance of as spun and annealed ribbons are investigated with various methods. In present alloys, increasing P content (cP ) can inhibit the precipitation of primary α-Fe and graphite phases, and promote the formation of eutectic α-Fe + Fe3 C + Fe3 P phases in ingots and annealed ribbons. With increasing annealing temperature (Tan ), the primary α-Fe grain size of the ribbons with cP = 4.5 at.% increases gradually and that of the ribbons with cP = 6.5 at.% increases firstly and then decreases. The degradation performance and reusability of the ribbons show a similar Tan -dependent behavior, which can be explained by the size effect of the galvanic cells. Meanwhile, the saturation magnetisation Bs and coercivity Hc of the ribbons with cP = 4.5 and 6.5 at.% increase with increasing Tan , showing a near-linear change of the reaction rate constant k against ln (Bs ·Hc ). This work not only studies the mechanism of improving degradation performance for FePC amorphous alloys by annealing treatment, but also reveals a correlation between degradation performance and magnetization performance of FePC alloys. [ABSTRACT FROM AUTHOR]- Published
- 2024
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24. Nightshift work and irregular menstrual cycle: 8-year follow-up cohort study.
- Author
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Kim, K, Lee, M Y, Chang, Y, and Ryu, S
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MENSTRUAL cycle ,SLEEP quality ,PROPORTIONAL hazards models ,COHORT analysis ,WORKING hours - Abstract
Background Irregular menstruation is a major health problem among women, although its association with nightshift work remains controversial. Aims To study the association between nightshift work and irregular menstrual cycle among female workers and investigate any differences according to sleep quality, working hours or obesity. Methods This study included female workers who underwent health examinations from 2012 to 2019. Nightshift work, working hours, sleep quality and menstrual cycles were assessed using self-administered questionnaires. Irregular menstrual cycle was defined as self-reported irregular or ≥36 days. Adjusted odds ratios and 95% confidence intervals (CIs) were calculated by multivariable logistic regression; adjusted hazard ratios (95% CIs) for incident irregular menstrual cycle were calculated by Cox proportional hazard models with time-dependent analysis. Results The study participants were 87 147 in the cross-sectional study and 41 516 in the longitudinal study. After adjusting for all covariates in the cross-sectional analyses, the odds ratio for prevalent irregular menstrual cycle among female nightshift workers versus the reference was 1.26 (95% CI 1.2–1.33). In the cohort study, the adjusted hazard ratio for incident irregular menstrual cycle among nightshift workers was 1.95 (95% CI 1.61–2.35) in the period after 6 years. No significant differences were observed among subgroups stratified by sleep quality, working hours or obesity. Conclusions Nightshift work is associated with an increased risk of both prevalent and incident irregular menstrual cycle in female workers without significant interactions by sleep quality, working hours or obesity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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25. How Successful Are Veterinary Weight Management Plans for Canine Patients Experiencing Poor Welfare Due to Being Overweight and Obese?
- Author
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Haddad, Kim K.
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REDUCING diets ,OBESITY ,WEIGHT loss ,PATIENTS' attitudes ,NUTRITION counseling ,CHILDHOOD obesity ,REGULATION of body weight - Abstract
Simple Summary: Poor welfare attributable to overweight and obesity is considered one of the most significant welfare issues affecting companion animals. Veterinarians play an important role in providing nutritional counseling and weight management advice, but successful weight loss is difficult to achieve and maintain. This research examines the level of veterinary engagement and the success of veterinary management plans for overweight and obese canines over a five-year period. The electronic medical records of overweight or obese canines from four San Francisco Bay Area small animal hospitals were statistically analyzed for level of veterinary engagement, weight loss success, prescription weight loss diet use, and comorbidities. The results suggest that veterinary engagement is variable and, even at the highest level, is not adequate to successfully combat overweight or obesity or result in improved welfare. Overweight and obesity is one of the most important and preventable animal welfare issues we face, yet successful treatment and management remain elusive. Overweight and obesity is one of the most significant health and welfare issues affecting companion animals and are linked to several serious medical conditions, reduced welfare, and shortened lifespan. The number of overweight and obese pets increases every year. Overweight and obesity are associated with multiple chronic diseases. Underlying causes include human-related and animal-related factors. Veterinarians encounter overweight and obese canine patients in daily practice and they play an important role in weight management. This research examines the level of veterinary engagement and the success of veterinary management plans for overweight and obese canines over a five-year period. Electronic medical records (EMRs) were collected for 500 canine patients assessed as either overweight or obese and statistically analyzed for level of veterinary engagement (VE), weight loss success, prescription weight loss diet (RX) use, and comorbidities. The average age at the beginning of the study was 61.5 months. A starting Body Condition Score (BCS) of 6 or 7 was most common (87.2%). Twelve different small and large dog breeds were most highly represented (61.1%). Average weight loss rates were low and more dogs gained rather than lost weight (56.5% vs. 43.5%). While VE is important, this study suggests current VE levels are not adequate to successfully combat overweight and obesity or result in improved animal welfare. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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26. On the issue of modeling the interaction of a pantograph with a contact wire.
- Author
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Kim, K., Ivanov, S., and Kolesova, A.
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PANTOGRAPH ,FREQUENCIES of oscillating systems ,ROLLING stock ,CATENARY - Abstract
The problem of improving the quality of the current collection process becomes particularly relevant at the high speeds of rolling stock movement. First of all, the quality of current collection is related to the interaction of the pantograph current collector with the contact wire. From the point of view of mechanics this is the process of the interaction of two oscillatory systems with a randomly varying degree of interaction. The analytical consideration of the dynamics of such interaction in the best case (if it is feasible at all) can only lead to probabilistic estimates of quantities interesting from the practical point of view. It was the motivating reason to develop some classes of the models of the reaction of the contact wire to the static and dynamic effects of the pantograph. We found the natural oscillation frequencies of the catenary and their corresponding eigen functions taking into account the structural elements providing an equilasticity of the catenary. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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27. Electromechanical device for heating diesel fuel locomotive.
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Kim, K. and Ivanov, S.
- Subjects
DIESEL locomotives ,ELECTROMECHANICAL devices ,FUEL filters ,STRUCTURAL reliability ,SPRAY nozzles ,DIESEL motors ,HEATING ,DIESEL fuels - Abstract
The difficulties of starting a diesel motor at negative ambient temperatures are known. It is primarily connected with the peculiarity of ignition of diesel fuel. At negative ambient temperatures the fuel becomes viscous, and its spraying by the nozzles becomes difficult. This problem is solved by installing various additional pre-starting fuel heaters on fuel filters, main pipeline or in the tank. They are autonomous electrical devices. In this paper we consider a new type of preheater. It simultaneously performs both heating and pumping of diesel fuel. This heater is designed on the basis of an electromechanical converter. One of the distinctive features of this device is the possibility of independent regulation of the amount of heating and pressure of the heated fuel. The analysis showed that the heater has the wide-regulating characteristics, provides the ability to obtain and maintain the specified temperature of the heated fuel, pressure and productivity. This device is high-tech and it is characterized by the high structural reliability. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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28. Patterns of Lipid Lowering Therapy Use Among Older Adults in a Managed Care Advantage Plan in the United States.
- Author
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Vadhariya, Aisha, Sharma, Manvi, Abughosh, Susan M., Birtcher, Kim K., Chen, Hua, Mohan, Anjana, and Johnson, Michael L.
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PATIENT aftercare ,STATINS (Cardiovascular agents) ,ANTILIPEMIC agents ,MANAGED care programs ,COMBINATION drug therapy ,RETROSPECTIVE studies ,ACQUISITION of data ,DRUG prescribing ,MEDICAL records ,DESCRIPTIVE statistics ,PHYSICIAN practice patterns ,TERMINATION of treatment ,OLD age - Abstract
Background: The prevalence of cardiovascular events is increasing. There are many new lipids lowering therapies available in recent years. Increased evidence through literature and guidelines suggests that the use of lipid lowering therapy (LLT) benefits patients who are at risk for cardiovascular events. Objective: The objective of this study was to describe the current LLT use as well as patterns of treatment modification among adults ≥ 65 years. Methods: A retrospective analysis of administrative claims data between January 2016 and May 2018 was conducted. Patients with a LLT refill and continuous enrollment during 1-year prior and 1-year follow-up were identified. The treatment episodes captured were interruption of therapy, intensity changes, dose changes, treatment augmentation, switching, and discontinuation. An analysis of treatment patterns among patients ≥75 years was also performed. Results: The study included 14,360 patients with a LLT of which 99% of patients were on statins as monotherapy or combination. Overall non-statin therapy use either as monotherapy or combination was 2.1%. There were significant differences among new initiators and existing users of therapy. Among prevalent users 57.4% had no changes in the follow-up period, 13.6% interrupted therapy, and 6.6% discontinued. Among new users, 47.9% patients had interrupted therapy, 25% had no changes, and 21.9% discontinued therapy. Conclusion: Most patients were on monotherapy and statins with low non-statin use. The new users among them were more likely to discontinue and interrupt therapy, highlighting the limitations and issues that older patients face that need to increase adherence. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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29. Neutron skin of 27Al with Skyrme and Korea-IBS-Daegu-SKKU density functionals.
- Author
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Gil, Hana, Hyun, Chang Ho, and Kim, K. S.
- Subjects
DENSITY functionals ,BORN approximation ,NEUTRONS ,NUCLEAR structure ,NUCLEAR models ,ELASTIC scattering ,ELECTRON scattering - Abstract
Recent measurement of the parity-violating (PV) asymmetry in the elastic electron scattering on 2 7 Al target evokes the interest in the distribution of the neutron in the nucleus. In this work, we calculate the neutron skin thickness ( R n p ) of 2 7 Al with nonrelativistic nuclear structure models. We focus on the role of the effective mass, symmetry energy and pairing force. Models are selected to have effective masses in the range (0.58–1.05) M where M is the nucleon mass in free space, and stiffness of the symmetry energy is varied by choosing the slope of the symmetry energy in the range 9.4–100.5 MeV. Effect of pairing force is investigated by calculating nuclear properties with and without pairing. With constant force pairing, we obtain R n p = 0. 0 0 1 –0.013 fm. The result is independent of the effective mass and symmetry energy. However, R n p is negative when the pairing force is switched off, so the pairing force plays an essential role to make R n p positive and constrained in a narrow range. We also calculate the PV asymmetry ( A pv ) in the elastic electron- 2 7 Al scattering in the Born approximation at the kinematics of the Qweak experiment. We obtain a very narrow-ranged result A pv = (2. 0 7 − 2. 0 9) × 1 0 − 6 . The result is consistent with the experiment and insensitive to the effective mass and symmetry energy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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30. Relationship Satisfaction, Co-Parenting, Spiritual Disclosure, and Religious/Spiritual Coping: Exploring Links to Parents' Mental Health following a Neonatal Intensive Care Experience.
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Brelsford, Gina M. and Doheny, Kim K.
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JOINT custody of children ,NEONATAL intensive care ,PARENTS ,MENTAL health ,SPIRITUALITY - Abstract
The birth of a child is often a joyous occasion, but when a family experiences a neonatal intensive care stay, there may be mental health and relationship implications. In this quantitative study, 162 former neonatal intensive care (NICU) parents completed surveys related to their anxiety (PSWQ; Meyer et al., 1990), stress (SASRQ-for NICU; Cardena et al., 2000), depression (CESD-R; Eaton et al., 2004), relationship satisfaction (RAS; Hendrick et al., 1998), and coparenting (Brief Measure of Co-Parenting; Feinberg et al., 2012) along with selfreports of religious/spiritual coping (Brief RCOPE; Pargament et al., 2011) and spiritual disclosure (SDS; Brelsford & Mahoney, 2008) in the couple relationship. Participants were acquired after soliciting names from a state Bureau of Health Statistics and mothers were contacted via mail with a second survey for her coparent/partner. Respondents to this survey were married or were living together as partners. Infants were born on average at 31.65 weeks' gestation and spent an average of 33.23 days in the NICU. The average time elapsed between NICU discharge and parent survey completion was 414 days. Analyses were conducted via SPSS Version 28 and results indicated that there were significant inverse correlations between parents' mental health and their relationship functioning (spiritual disclosure, relationship satisfaction, and co-parenting). Moreover, parents' mental health challenges were significantly related to increased use of negative religious/spiritual coping. Finally, after accounting for relationship functioning, parents' use of negative religious coping had a significant link to their mental health outcomes. Thus, when parents are experiencing difficulties with their mental health after a NICU experience, they may struggle more with their marriage, co-parenting, and engage in more negative religious/spiritual coping. Therefore, additional research is needed on ways to support parents' mental health, relational functioning, and religious/spiritual lives following a NICU experience. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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31. Not-so-fast Kepler-1513: a perturbing planetary interloper in the exomoon corridor.
- Author
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Yahalomi, Daniel A, Kipping, David, Nesvorný, David, Dalba, Paul A, Benni, Paul, Cacho-Negrete, Ceiligh, Collins, Karen, Earwicker, Joel T, Lewis, John Arban, McLeod, Kim K, Schwarz, Richard P, and Wang, Gavin
- Subjects
PLANETARY orbits ,ORBITS (Astronomy) ,STELLAR activity ,NATURAL satellites ,PHENOMENOLOGICAL theory (Physics) ,PLANETARY mass - Abstract
Transit timing variations (TTVs) can be induced by a range of physical phenomena, including planet–planet interactions, planet–moon interactions, and stellar activity. Recent work has shown that roughly half of moons would induce fast TTVs with a short period in the range of 2–4 orbits of its host planet around the star. An investigation of the Kepler TTV data in this period range identified one primary target of interest, Kepler-1513 b. Kepler-1513 b is a |$8.05^{+0.58}_{-0.40}$| R
⊕ planet orbiting a late G-type dwarf at |$0.53^{+0.04}_{-0.03}$| au. Using Kepler photometry, this initial analysis showed that Kepler-1513 b's TTVs were consistent with a moon. Here, we report photometric observations of two additional transits nearly a decade after the last Kepler transit using both ground-based observations and space-based photometry with TESS. These new transit observations introduce a previously undetected long period TTV, in addition to the original short period TTV signal. Using the complete transit data set, we investigate whether a non-transiting planet, a moon, or stellar activity could induce the observed TTVs. We find that only a non-transiting perturbing planet can reproduce the observed TTVs. We additionally perform transit origami on the Kepler photometry, which independently applies pressure against a moon hypothesis. Specifically, we find that Kepler-1513 b's TTVs are consistent with an exterior non-transiting ∼Saturn mass planet, Kepler-1513 c, on a wide orbit, |$\sim 5~{{\ \rm per \, cent}}$| outside a 5:1 period ratio with Kepler-1513 b. This example introduces a previously unidentified cause for planetary interlopers in the exomoon corridor, namely an insufficient baseline of observations. [ABSTRACT FROM AUTHOR]- Published
- 2024
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32. Relationships Between Dress and Gender Identity: LGBTQIA +.
- Author
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Adomaitis, Alyssa Dana, Saiki, Diana, Johnson, Kim K. P., Sahanoor, Rafi, and Attique, Arsha
- Abstract
This article examines the relationship between dress and gender identity, with a focus on the LGBTQIA+ community. It explores the evolving concept of gender identity and the distinction between gender identity and expression. The study investigates how individuals who identify as non-cisgender use dress to express their gender identity and the challenges they face in doing so. The research utilizes interviews with members of the LGBTQIA+ community and analyzes the data using self-verification theory and a phenomenological approach. The study reveals that participants in the non-binary gender community use clothing, accessories, and body modifications to announce their gender, but they also encounter barriers such as stereotypes and limitations. The findings emphasize the importance of education, awareness, and inclusive dress codes to support diverse gender identities. Further research is needed to explore the experiences of LGBTQIA+ individuals in different contexts and during transitioning. [Extracted from the article]
- Published
- 2024
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33. Magnetocardiography at rest predicts cardiac death in patients with acute chest pain.
- Author
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Wessel, N., Kim, J. S., Joung, B. Y., Ko, Y. G., Dischl, D., Gapelyuk, A., Lee, Y. H., Kim, K. W., Park, J. W., and Landmesser, U.
- Published
- 2023
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34. A microcosm experiment on sediment remediation: microbial community assessment in sediment in presence of granulated coal ash.
- Author
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Patil, M. P., Woo, H.-E., Lee, I.-C., Kim, J.-O., and Kim, K.
- Subjects
MICROBIAL remediation ,MICROBIAL communities ,SEDIMENTS ,OXIDATION-reduction potential ,MICROORGANISM populations ,MICROBIAL diversity - Abstract
Coastal areas contain buildup of mixed organic and inorganic contaminants, which promote deterioration or sediment and impairment of benthic life. Hence, it is necessary to develop a method for sediment remediation and to promote the ecosystem. In this study, Granulated Coal Ash (GCA) was used as a covering material for the remediation of sediment. Our results indicate an increase in pH and oxidation–reduction potential, as well as a decrease in the concentrations of phosphate and hydrogen sulfide in the sediment and overlying water. The top three phyla observed based on 16S rRNA gene amplicon sequencing were Proteobacteria, Bacteroidetes, and Firmicutes. Further, as a consequence of physicochemical changes in the sediments, we observed a significant change in the relative abundance of Deltaproteobacteria, Epsilonproteobacteria, and Gammaproteobacteria. In conclusion, GCA is a promising covering material for limiting contaminants in sediment and overlying water, and promoting the diversity of microbial populations for sediment remediation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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35. Properties of ceramics SiC with sintering additive Al2O3-Y2O3-ZrO2.
- Author
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Lysenkov, A. S., Frolova, M. G., Perevislov, S. N., Kim, K. A., Petrakova, N. V., Kaplan, M. A., Melnikov, M. D., and Kargin, Yu. F.
- Subjects
SINTERING ,CERAMIC materials ,STEREOLITHOGRAPHY ,HOT pressing ,THERMAL expansion ,SILICON carbide ,CERAMICS - Abstract
The effect of the Al
2 O3 −Y2 O3 −ZrO2 sintering additive on compaction and mechanical properties of silicon carbide ceramics was studied in this work. The sintering additive was obtained by plasma-chemical synthesis. Sintering ceramic was carried out by hot pressing in the temperature range 1700-1800°C. With an increase in temperature, an increase in density and mechanical properties occurs. The ceramic material has a linear thermal expansion coefficient in the temperature range 20-1600°C equal to 3.9х10−6 К−1 . [ABSTRACT FROM AUTHOR]- Published
- 2023
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36. Hot pressed AlON ceramic.
- Author
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Lysenkov, A. S., Frolova, M. G., Kim, K. A., Petrakova, N. V., Ivicheva, S. N., Akhmadullina, N. S., Ovsyannikov, N. A., Melnikov, M. D., and Kargin, Yu. F.
- Subjects
CERAMICS ,SCANNING electron microscopy ,X-ray microscopy ,HOT pressing ,ATMOSPHERIC nitrogen - Abstract
Monophase ceramics based on silicon oxonitride was obtained in one technological stage, combining the synthesis of the aluminum oxonitride phase and its further densification by hot pressing at 1850°C in a nitrogen atmosphere. The obtained samples were characterized by scanning electron microscopy and X-ray phase analysis; the mechanical properties of the ceramic samples were measured. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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37. Tripogon loliiformis tolerates rapid desiccation after metabolic and transcriptional priming during initial drying.
- Author
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Okemo, Pauline A., Njaci, Isaac, Kim, Young-Mo, McClure, Ryan S., Peterson, Matthew J., Beliaev, Alexander S., Hixson, Kim K., Mundree, Sagadevan, and Williams, Brett
- Subjects
SALICYLIC acid ,CROPS ,BIOMASS production ,POWER resources ,AMINO acids ,CROP growth ,METABOLOMICS - Abstract
Crop plants and undomesticated resilient species employ different strategies to regulate their energy resources and growth. Most crop species are sensitive to stress and prioritise rapid growth to maximise yield or biomass production. In contrast, resilient plants grow slowly, are small, and allocate their resources for survival in challenging environments. One small group of plants, termed resurrection plants, survive desiccation of their vegetative tissue and regain full metabolic activity upon watering. However, the precise molecular mechanisms underlying this extreme tolerance remain unknown. In this study, we employed a transcriptomics and metabolomics approach, to investigate the mechanisms of desiccation tolerance in Tripogon loliiformis, a modified desiccation-tolerant plant, that survives gradual but not rapid drying. We show that T. loliiformis can survive rapid desiccation if it is gradually dried to 60% relative water content (RWC). Furthermore, the gene expression data showed that T. loliiformis is genetically predisposed for desiccation in the hydrated state, as evidenced by the accumulation of MYB, NAC, bZIP, WRKY transcription factors along with the phytohormones, abscisic acid, salicylic acid, amino acids (e.g., proline) and TCA cycle sugars during initial drying. Through network analysis of co-expressed genes, we observed differential responses to desiccation between T. loliiformis shoots and roots. Dehydrating shoots displayed global transcriptional changes across broad functional categories, although no enrichment was observed during drying. In contrast, dehydrating roots showed distinct network changes with the most significant differences occurring at 40% RWC. The cumulative effects of the early stress responses may indicate the minimum requirements of desiccation tolerance and enable T. loliiformis to survive rapid drying. These findings potentially hold promise for identifying biotechnological solutions aimed at developing drought-tolerant crops without growth and yield penalties. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Metabolomic, photoprotective, and photosynthetic acclimatory responses to post‐flowering drought in sorghum.
- Author
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Baker, Christopher R., Patel‐Tupper, Dhruv, Cole, Benjamin J., Ching, Lindsey G., Dautermann, Oliver, Kelikian, Armen C., Allison, Cayci, Pedraza, Julie, Sievert, Julie, Bilbao, Aivett, Lee, Joon‐Yong, Kim, Young‐Mo, Kyle, Jennifer E., Bloodsworth, Kent J., Paurus, Vanessa, Hixson, Kim K., Hutmacher, Robert, Dahlberg, Jeffery, Lemaux, Peggy G., and Niyogi, Krishna K.
- Subjects
SORGHUM ,DROUGHTS ,FLOWERING time ,METABOLOMICS ,RAINFALL ,DROUGHT tolerance ,LEAF area ,RNA sequencing - Abstract
Climate change is globally affecting rainfall patterns, necessitating the improvement of drought tolerance in crops. Sorghum bicolor is a relatively drought‐tolerant cereal. Functional stay‐green sorghum genotypes can maintain green leaf area and efficient grain filling during terminal post‐flowering water deprivation, a period of ~10 weeks. To obtain molecular insights into these characteristics, two drought‐tolerant genotypes, BTx642 and RTx430, were grown in replicated control and terminal post‐flowering drought field plots in California's Central Valley. Photosynthetic, photoprotective, and water dynamics traits were quantified and correlated with metabolomic data collected from leaves, stems, and roots at multiple timepoints during control and drought conditions. Physiological and metabolomic data were then compared to longitudinal RNA sequencing data collected from these two genotypes. The unique metabolic and transcriptomic response to post‐flowering drought in sorghum supports a role for the metabolite galactinol in controlling photosynthetic activity through regulating stomatal closure in post‐flowering drought. Additionally, in the functional stay‐green genotype BTx642, photoprotective responses were specifically induced in post‐flowering drought, supporting a role for photoprotection in the molecular response associated with the functional stay‐green trait. From these insights, new pathways are identified that can be targeted to maximize yields under growth conditions with limited water. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
39. Interplay between driveline infection, vessel wall inflammation, cerebrovascular events and mortality in patients with left ventricular assist device.
- Author
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Hupe, Juliane, Worthmann, Hans, Ravenberg, Kim K., Grosse, Gerrit M., Ernst, Johanna, Haverich, Axel, Bengel, Frank M., Weissenborn, Karin, Schmitto, Jan D., Hanke, Jasmin S., Derlin, Thorsten, and Gabriel, Maria M.
- Subjects
HEART assist devices ,THORACIC aorta ,LOGISTIC regression analysis ,MORTALITY risk factors ,BONE marrow ,TRANSCRANIAL magnetic stimulation - Abstract
In patients with left ventricular assist device (LVAD), infections and thrombotic events represent severe complications. We investigated device-specific local and systemic inflammation and its impact on cerebrovascular events (CVE) and mortality. In 118 LVAD patients referred for
18 F-FDG-PET/CT, metabolic activity of LVAD components, thoracic aortic wall, lymphoid and hematopoietic organs, was quantified and correlated with clinical characteristics, laboratory findings, and outcome. Driveline infection was detected in 92/118 (78%) patients by18 F-FDG-PET/CT. Activity at the driveline entry site was associated with increased signals in aortic wall (r = 0.32, p < 0.001), spleen (r = 0.20, p = 0.03) and bone marrow (r = 0.20, p = 0.03), indicating systemic interactions. Multivariable analysis revealed independent associations of aortic wall activity with activity of spleen (β = 0.43, 95% CI 0.18–0.68, p < 0.001) and driveline entry site (β = 0.04, 95% CI 0.01–0.06, p = 0.001). Twenty-two (19%) patients suffered CVE after PET/CT. In a binary logistic regression analysis metabolic activity at the driveline entry site missed the level of significance as an influencing factor for CVE after adjusting for anticoagulation (OR = 1.16, 95% CI 1–1.33, p = 0.05). Metabolic activity of the subcutaneous driveline (OR = 1.13, 95% CI 1.02–1.24, p = 0.016) emerged as independent risk factor for mortality. Molecular imaging revealed systemic inflammatory interplay between thoracic aorta, hematopoietic organs, and infected device components in LVAD patients, the latter predicting CVE and mortality. [ABSTRACT FROM AUTHOR]- Published
- 2023
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40. A practical option for the selection of suitable plants for the management of airborne particulate matter (PM).
- Author
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Tiwari, A., Gajbhiye, T., Pandey, M., Tirkey, A., Kim, K. H., and Pandey, S. K.
- Subjects
PLANT selection ,PARTICULATE matter ,SCANNING electron microscopy ,IMAGE analysis ,ROUGH surfaces - Abstract
In this study, PM deposition on plants was quantitatively analyzed in an urban roadside environment of Bilaspur, Chhattisgarh (India). The leaf wash method was used to obtain PM retention capacity in the respirable and non-respirable ranges. Additionally, micrographs of plant leaves were obtained by scanning electron microscopy (SEM) and used to quantify PM in three size ranges (0.2–2.5 μm, 2.5–10 μm, and 10–100 μm). There were large differences in PM retention capacity between our results and the conventional method. In contrast to the general expectation, smooth surface leaves were found to remove PM in a respirable range more efficiently than rough surface leaves. Polyalthia longifolia showed the highest retention capacity for respirable PM by a conventional leaf wash method, while Dalbergia sissoo showed the best results based on our approach. The image analysis based on SEM micrographs indicates a specific pattern for the accumulation of PM in distinct size ranges. Overall, the results of this study suggest that an image-based quantification can be used as an effective option for a rapid and superior selection of the plant species needed for urban road greening programs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. OsCM regulates rice defence system in response to UV light supplemented with drought stress.
- Author
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Jan, R., Kim, N., Asaf, S., Lubna, Asif, S., Du, X.‐X., Kim, E.‐G., Jang, Y.‐H., and Kim, K.‐M.
- Subjects
PHENYLALANINE ammonia lyase ,QUERCETIN ,DROUGHTS ,GLUTAMIC acid ,ASPARTIC acid ,RICE ,CROPS - Abstract
Studies on plant responses to combined abiotic stresses are very limited, especially in major crop plants. The current study evaluated the response of chorismate mutase overexpressor (OxCM) rice line to combined UV light and drought stress.The experiments were conducted in pots in a growth chamber, and data were assessed for gene expression, antioxidant and hormone regulation, flavonoid accumulation, phenotypic variation, and amino acid accumulation.Wild‐type (WT) rice had reduced the growth and vigour, while transgenic rice maintained growth and vigour under combined UV light and drought stress. ROS and lipid peroxidation analysis revealed that chorismate mutase (OsCM) reduced oxidative stress mediated by ROS scavenging and reduced lipid peroxidation. The combined stresses reduced biosynthesis of total flavonoids, kaempferol and quercetin in WT plants, but increased significantly in plants with OxCM. Phytohormone analysis showed that SA was reduced by 50% in WT and 73% in transgenic plants, while ABA was reduced by 22% in WT plants but increased to 129% in transgenic plants. Expression of chorismate mutase regulates phenylalanine biosynthesis, UV light and drought stress‐responsive genes, e.g., phenylalanine ammonia lyase (OsPAL), dehydrin (OsDHN), dehydration‐responsive element‐binding (OsDREB), ras‐related protein 7 (OsRab7), ultraviolet‐B resistance 8 (OsUVR8), WRKY transcription factor 89 (OsWRKY89) and tryptophan synthase alpha chain (OsTSA). Moreover, OsCM also increases accumulation of free amino acids (aspartic acid, glutamic acid, leucine, tyrosine, phenylalanine and proline) and sodium (Na), potassium (K), and calcium (Ca) ions in response to the combined stresses.Together, these results suggest that chorismate mutase expression induces physiological, biochemical and molecular changes that enhance rice tolerance to combined UV light and drought stresses. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
42. Si3N4/TiN Ceramic Composites Produced by Hot Pressing.
- Author
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Kim, K. A., Lysenkov, A. S., Frolova, M. G., and Kargin, Yu. F.
- Subjects
SILICON nitride ,TITANIUM composites ,CERAMICS ,HOT pressing ,NITRIDATION ,POWDERS ,TITANIUM ,MICROHARDNESS - Abstract
Si
3 N4 /TiN ceramic composites have been prepared by hot pressing in a nitrogen atmosphere using fine Si3 N4 and Ti powders and CaO–Al2 O3 sintering aids and investigated. The results demonstrate that hot pressing was accompanied by titanium nitridation, yielding titanium nitride with the composition TiN0.9 . Reaction between silicon nitride and the sintering aid led to the formation of a Ca-α-SiAlON with the composition Ca0.67 (Si10 Al2 )(N15.3 O0.7 ). In addition to the major phases, calcium aluminosilicate with the composition Ca3 Al2 Si3 O12 was identified. Increasing the percentage of titanium nitride in the composites prepared at a temperature of 1650°C led to an increase in their density and Vickers microhardness: from 3.18 ± 0.03 to 4.33 ± 0.03 g/cm3 and from 17 ± 1.1 to 29.4 ± 0.9 GPa, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2023
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43. Phase Composition and Physicomechanical Properties of β-Sialons Prepared Using NaF as a Sintering Aid.
- Author
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Akhmadullina, N. S., Sirotinkin, V. P., Kim, K. A., Lysenkov, A. S., Frolova, M. G., Fedorov, S. V., Ovsyannikov, N. A., Ivicheva, S. N., and Kargin, Yu. F.
- Subjects
MICROHARDNESS ,SINTERING ,PHASE change materials ,SODIUM fluoride - Abstract
We have studied the effect of sodium fluoride as a sintering aid for β-sialons on the phase composition and physicomechanical properties of Si
5 AlON7 and Si4 Al2 O2 N6 . Two-step high-temperature firing of the β-sialons in the presence of NaF under a nitrogen atmosphere has been shown to cause no significant changes in the phase composition of the materials. The density and microhardness of the materials prepared using 0.5 and 5.0 wt % NaF are lower than those of the materials prepared without sintering aids, but the bending strength is higher by up to 14.3% in the case of Si5 AlON7 prepared using 0.5 wt % NaF and by 4.9% in the case of Si4 Al2 O2 N6 prepared using 5.0 wt % NaF. [ABSTRACT FROM AUTHOR]- Published
- 2023
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44. Minimum Fire Size for Hydrogen Storage Tank Fire Test Protocol and Design Guides for Hydrogen Bus Established via Risk-Based Approach.
- Author
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Kim, E., Kim, W. K., Kim, K. S., Park, G. T., Jun, H. B., Jung, C. H., and Kim, S. W.
- Subjects
FIRE testing ,HYDROGEN storage ,STORAGE tanks ,FIRE exposure ,TEST design ,ELECTRIC motor buses ,BUSES ,FLAME spread - Abstract
As part of the United Nations Global Technical Regulation No. 13 (UN GTR #13), vehicle fire safety is validated using a localized and engulfing fire test methodology and currently, updates are being considered in the on-going Phase 2 development stage. The GTR#13 fire test is designed to verify the performance of a hydrogen storage system of preventing rupture when exposed to service-terminating condition of fire situation. The test is conducted in two stages—localized flame exposure at a location most challenging for thermally-activated pressure relief device(s) (TPRDs) to respond for 10 min. followed by engulfing fire exposure until the system vents and the pressure falls to less than 1 MPa or until "time out" (30 min. for light-duty vehicle containers and 60 min. for heavy-duty vehicle containers). The rationale behind this two-stage fire test is to ensure that even when fire sizes are small and TPRDs are not responding the containers have fire resistance to withstand or fire sensitivity to respond to a localized fire to avoid system rupture. In this study, appropriate fire sizes for localized and engulfing fire tests in GTR#13 are evaluated by considering actual fire conditions in a hydrogen-powered electric city bus. Quantitative risk analysis is conducted to develop various fire accident scenarios including regular bus fire, battery fire, and hydrogen leak fire. Frequency and severity analyses are performed to determine the minimum fire size required in GTR#13 fire test and the design guides to ensure hydrogen storage tank safety in hydrogen-powered electric city buses. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Spacesuit Center of Gravity Assessments for Partial Gravity EVA Simulation in an Underwater Environment.
- Author
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Vu, Linh Q., Shaw, James H., Kim, K. Han, Benson, Elizabeth, and Rajulu, Sudhakar L.
- Subjects
CENTER of mass ,GRAVITY ,BUOYANCY ,UNDERWATER acoustics ,EXTREME environments ,PREDICTION models - Abstract
Objective: The objective is to analytically determine the expected CG and build hardware to measure and verify the suited subject's CG for lunar extravehicular activity (EVA) training in an underwater environment. Background: For lunar EVAs, it is necessary for astronauts to train with a spacesuit in a simulated partial gravity environment. NASA's Neutral Buoyancy Laboratory (NBL) can provide these conditions by producing negative buoyancy for a submerged suited subject. However, it is critical that the center of gravity (CG) for the human-spacesuit system to be accurate for conditions expected during planetary EVAs. Methods: An underwater force-transducer system and individualized human-spacesuit model was created to provide real-time measurement of CG, including recommendations for weight placement locations and quantity of weight needed on the spacesuit to achieve a realistic lunar spacesuit CG. This method was tested with four suited subjects. Results: Across tested weighout configurations, it was observed that an aft and high CG location will have large postural differences when compared to low and fore CG locations, highlighting the importance of having a proper CG. The system had an accuracy of ±5lbs of the total lunar weight and within ± 15 cm for fore-aft and left-right CG directions of the model predictions. Conclusion: The developed method offers analytical verification of the suited subject's CG and improves simulation quality of lunar EVAs. Future suit design can also benefit by recommending hardware changes to create ideal CG locations that improve balance and mobility. Application: The developed methodology can be used to verify a proper CG location in future planetary EVA simulations such as different reduced gravity training analogs (e.g. active cable offloading systems). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Anthropometric Changes in Spaceflight.
- Author
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Young, Karen S., Kim, K. Han, and Rajulu, Sudhakar
- Subjects
ERGONOMICS ,ASTRONAUTS ,SPACE flight ,SPACE suits ,LENGTH measurement ,STATURE ,SPACE stations - Abstract
Objective: This study aims to identify the change in anthropometric measurements during spaceflight due to microgravity exposure. Background: Comprehensive and accurate anthropometric measurements are crucial to assess body shape and size changes in microgravity. However, only limited anthropometric data have been available from the astronauts in spaceflight. Methods: A new photogrammetry-based technique in combination with a tape-measure method was used for anthropometric measurements from nine crewmembers on the International Space Station. Measurements included circumference and height for body segments (chest, waist, bicep, thigh, calf). The time-dependent variations were also assessed across pre-, in-, and postflight conditions. Results: Stature showed a biphasic change with up to 3% increase at the early flight phase, followed by a steady phase during the remaining flight. Postflight measurements returned to a similar level of the preflight. Other linear measurements, including acromion height, showed similar trends. The chest, hip, thigh, and calf circumferences show overall decrease during the flight up to 11%, then returned close to the preflight measurement at postflight. Conclusion: The measurements from this study provide critical information for the spacesuit and hardware design. The ground-based assessments for spacesuit fit needs to be revalidated and adjusted for in-flight extravehicular activities from this data. Application: These data can be useful for space suit design as well as habitat, vehicle, and additional microgravity activities such as exercise, where the body shape changes can affect fit, performance, and human factors of the overall design. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Interaction of SiC with Al2O3−(t + m)ZrO2(Y2O3) Oxide Composition.
- Author
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Frolova, M. G., Lysenkov, A. S., Perevislov, S. N., Petrakova, N. V., Kim, K. A., Sevost'yanov, M. A., Ivannikov, A. Yu., Mel'nikov, M. D., and Kargin, Yu. F.
- Abstract
We employed contact alloying in the range 1000–1860°С to study the reaction specifics between SiC and Al
2 O3 −(t + m)ZrO2 (Y2 O3 ) oxide composition. Real-time experiments with photographic recording of the changing size and shape of the Al2 O3 −(t + m)ZrO2 (Y2 O3 ) sample on a SiC ceramic substrate showed that Al2 O3 −(t + m)ZrO2 (Y2 O3 ) compositions react with the silicon carbide substrate in the range 1720–1860°С to melt and penetrate into (impregnate) the substrate. X-ray powder diffraction patterns were measured for samples taken from the contact area of the oxide composition with SiC directly on the substrate and in a chipped-off <1-mm-deep near-surface layer. ZrС, Al2 Y4 O9 , and Al3.21 Si0.47 were formed in the contact area via redox reactions involving oxide melt, in addition to 6H-SiC, Si and Al2 O3 , t-ZrO2 phases, which are the initial components of the substrate and oxide composition, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2023
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48. Susceptible-Infected-Susceptible Dynamics with Mitigation in Connection of Infected Population.
- Author
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Kim, K. M., Dias, C., and Hase, M. O.
- Abstract
The susceptible-infected-susceptible epidemic model is analyzed through a degree-based mean-field approach. In this work, a mitigation factor is introduced in the probability of finding an infected individual following an edge. This modification simulates situations where the infected population reduces its participation in the dynamics of disease propagation, as may happen with the seclusion or hospitalization of infected individuals. A detailed investigation of this new model and its comparison to the original one (without the mitigation factor) was performed on the Barabási-Albert network, where some important results were analytically accessible. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Arterial Spin-Labeling MR Imaging for the Differential Diagnosis of Venous-Predominant AVMs and Developmental Venous Anomalies.
- Author
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Yoo, D. H., Sohn, C.-H., Kang, H.-S., Cho, Y. D., and Kim, K. M.
- Published
- 2023
- Full Text
- View/download PDF
50. New Perspective on Phase Space Density Analysis for Outer Radiation Belt Enhancements: The Influence of MeV Electron Injections.
- Author
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Kim, H.‐J., Kim, K.‐C., Noh, S.‐J., Lyons, L., Lee, D.‐Y., and Choe, W.
- Subjects
RADIATION belts ,PHASE space ,ELECTRONS ,TERRESTRIAL radiation ,ELECTRON traps - Abstract
Observation of growing phase space density (PSD) peak in the outer electron radiation belt has been considered evidence for local wave‐driven acceleration as a primary cause of radiation belt enhancement. However, recent studies showed that strong substorm‐associated MeV electron injections can also cause significant radiation belt enhancements on fast timescales (∼10s min). Such rapid enhancements pose challenges for determining true spatial PSD profiles. To address this, we conduct a detailed spatiotemporal analysis of electron flux and PSD during an enhancement event, using Van Allen Probes data. Our analysis reveals rapid and intermittent flux enhancements. During these rapid enhancements, inbound spacecraft observed false PSD peaks, due to spacecraft's relatively slow movement. However, we identify time intervals of stable fluxes between enhancements, enabling us to determine quasi‐stationary PSD profiles with no noticeable peaks. This study provides new insights into accurate PSD analysis, critical for understanding the mechanisms underlying radiation belt enhancements. Plain Language Summary: Radiation belt physics studies the origin and dynamics of high‐energy electrons trapped in the Earth's radiation belts. The radial profiles of these electrons' phase space density (PSD) are essential parameters for investigating their origin and dynamics. Outward‐increasing PSD profiles indicate that electrons have been transported radially (injections) from outside the radiation belt, while locally peaked profiles suggest that they were generated locally within the belt. Obtaining accurate PSD profiles is challenging due to significant temporal changes in electron flux, particularly rapid flux enhancements from injections as observed in recent studies. To examine the impact of rapid flux enhancements on PSD analysis, we closely tracked electron flux changes in space and time during an enhancement event using data from NASA's Van Allen Probes. Our results show that inbound spacecraft can observe falsely peaked PSD profiles during rapid flux enhancements, which are temporal artifacts from relatively slower spacecraft motion. By identifying time intervals of stable electron flux between enhancements, we were able to determine the true spatial PSD profiles, which overall exhibited outward‐increasing trends, consistent with injections. Our findings offer new perspective on accurately determining PSD radial profiles, which is essential for unraveling the origins of high‐energy electrons in the Earth's radiation belts. Key Points: Rapid and intermittent electron enhancement pattern significantly impacts phase space density (PSD) analysisInbound spacecraft can observe a temporal PSD peak during rapid electron enhancements driven by injectionsQuasi‐stationary time intervals between enhancements enable accurate determination of PSD radial profiles [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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