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1.
Nat Commun ; 15(1): 3990, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734685

RESUMEN

The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.

2.
Phys Rev Lett ; 131(20): 201802, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039466

RESUMEN

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7 kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

3.
J Hosp Infect ; 131: 228-233, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36460176

RESUMEN

BACKGROUND: There have been limited data on the risk of onward transmission from individuals with Omicron variant infections who return to work after a 5-day isolation. AIM: To evaluate the risk of transmission from healthcare workers (HCWs) with Omicron variant who returned to work after a 5-day isolation and the viable-virus shedding kinetics. METHODS: This investigation was performed in a tertiary care hospital, Seoul, South Korea. In a secondary transmission study, we retrospectively reviewed the data of HCWs confirmed as COVID-19 from March 14th to April 3rd, 2022 in units with five or more COVID-19-infected HCWs per week. In the viral shedding kinetics study, HCWs with Omicron variant infection who agreed with daily saliva sampling were enrolled between February and March, 2022. FINDINGS: Of the 248 HCWs who were diagnosed with COVID-19 within 5 days of the return of an infected HCW, 18 (7%) had contact with the returned HCW within 1-5 days after their return. Of these, nine (4%) had an epidemiologic link other than with the returning HCW, and nine (4%) had contact with the returning HCW, without any other epidemiologic link. In the study of the kinetics of virus shedding (N = 32), the median time from symptom onset to negative conversion of viable virus was four days (95% confidence interval: 3-5). CONCLUSION: Our data suggest that the residual risk of virus transmission after 5 days of isolation following diagnosis or symptom onset is low.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Estudios Retrospectivos , Cinética , Personal de Salud
4.
Nature ; 609(7926): 269-275, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36071190

RESUMEN

Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.

5.
Osteoarthritis Cartilage ; 30(9): 1210-1221, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35513246

RESUMEN

OBJECTIVE: This study was performed to characterize selected rhodanine derivatives as potential preclinical disease-modifying drugs for experimental osteoarthritis (OA) in mice. METHODS: Three rhodanine derivatives, designated rhodanine (R)-501, R-502, and R-503, were selected as candidate OA disease-modifying drugs. Their effects were evaluated by intra-articular (IA) injection in OA mouse models induced by DMM (destabilization of the medial meniscus) or adenoviral overexpression in joint tissues of hypoxia-inducible factor (HIF)-2α or zinc importer ZIP8. The regulatory mechanisms impacted by the rhodanine derivatives were examined in primary-culture chondrocytes and fibroblast-like synoviocytes (FLS). RESULTS: All three rhodanine derivatives inhibited OA development caused by DMM or overexpression of HIF-2α or ZIP8. Compared to vehicle-treated group, for example, IA injection of R-501 in DMM-operated mice reduced median OARSI grade from 3.78 (IQR 3.00-5.00) to 1.89 (IQR 0.94-2.00, P = 0.0001). R-502 and R-503 also reduced from 3.67 (IQR 2.11-4.56) to 2.00 (IQR 1.00-2.00, P = 0.0030) and 2.00 (IQR 1.83-2.67, P = 0.0378), respectively. Mechanistically, the rhodanine derivatives inhibited the nuclear localization and transcriptional activity of HIF-2α in chondrocytes and FLS. They did not bind to Zn2+ or modulate Zn2+ homeostasis in chondrocytes or FLS; instead, they inhibited the nuclear localization and transcriptional activity of the Zn2+-dependent transcription factor, MTF1. HIF-2α, ZIP8, and interleukin-1ß could upregulate matrix-degrading enzymes in chondrocytes and FLS, and the rhodanine derivatives inhibited these effects. CONCLUSION: IA administration of rhodanine derivatives significantly reduced OA pathogenesis in various mouse models, demonstrating that these derivatives have disease-modifying therapeutic potential against OA pathogenesis.


Asunto(s)
Cartílago Articular , Osteoartritis , Rodanina , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cartílago Articular/patología , Condrocitos/metabolismo , Modelos Animales de Enfermedad , Ratones , Osteoartritis/metabolismo , Preparaciones Farmacéuticas/metabolismo , Rodanina/metabolismo , Rodanina/farmacología
6.
Int J Dent ; 2021: 3433343, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34887924

RESUMEN

AIM: To investigate the root canal anatomy of Burmese (Myanmar) permanent maxillary first molar (BMFM) with micro-computed tomography. Methodology. One hundred and one extracted BMFMs were scanned by a SkyScan 1272 scanner (Bruker microCT, Belgium) and reconstructed with NRecon software (Bruker microCT). CTAn software (Bruker microCT) was used to create 3D models of root and internal canal anatomy, while CTVol software (Bruker microCT) was used to visualize 3D models. In each root, Vertucci's canal types, incidence and location of the lateral canal, incidence, location, and type of isthmus, and number and position of foramina were examined. RESULTS: In 101 specimens, 83 (82.18%) mesiobuccal roots had multiple canals. The most common canal type is type IV (45.5%), followed by type II (17.8%) and I (17.8%) canals. Type III, V, VI, VII, and VIII canals are less than 10% in total. Seven additional canal types were seen for 10% in total. Fourteen (13.86%) distobuccal roots had multiple canals, and the predominant canal type is type I (86.1%), followed by type II (5.9%) and V (4%) canals. Three additional canal types were observed for 4% in total. All palatal roots possessed the simplest type I canal. Apical ramification occurred in 69 mesiobuccal roots (68.3%), 36 distobuccal roots (35.6%), and 37 palatal roots (36.6%). A total of 240 lateral canals were observed in 101 specimens. Each specimen had 2.38 ± 2.22 lateral canals on average. The highest incidence, 136 (56.67%) lateral canals, occurred in the mesiobuccal root, followed by 57 (23.75%) and 47 (19.58%) lateral canals from the distobuccal root and the palatal root, respectively. Each specimen had 6.17 ± 2.42 foramina. Mesiobuccal root had the highest incidence of apical foramina compared to other roots. Seventy-two mesiobuccal roots (71.29%) had isthmus, while only 7 distobuccal roots (6.93%) had isthmus somewhere along the root. CONCLUSIONS: The root canal anatomy of BMFM was quite complex, especially in the mesiobuccal root. The predominant canal type was Vertucci type IV in the mesiobuccal root and type I in the distobuccal and palatal roots. In addition, this micro-computed tomography study disclosed complemented canal types and a higher prevalence of lateral canal than the previous studies.

7.
AJNR Am J Neuroradiol ; 42(6): 1157-1162, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33737264

RESUMEN

BACKGROUND AND PURPOSE: In certain cases of pediatric patients with Moyamoya disease undergoing encephaloduroarteriosynangiosis (EDAS) treatment, the posterior auricular artery can be used as an alternative when the parietal branch of the superficial temporal artery is unavailable. In this study, anatomic variations of the superficial temporal and posterior auricular arteries in pediatric patients with Moyamoya disease and postoperative outcomes of posterior auricular artery-EDAS are explored. MATERIALS AND METHODS: Medical records of 572 patients with Moyamoya disease who underwent surgical procedures from 2007 to 2017 at the Seoul National University Children's Hospital were reviewed. Anatomic classifications of the superficial temporal and posterior auricular arteries were based on previous classifications. Postoperative hemodynamic changes of posterior auricular artery-EDAS were analyzed using the Matsushima grade. Also, Karnofsky Performance Scale and mRS scores of posterior auricular artery-EDAS cases were reviewed to identify postoperative clinical outcomes. RESULTS: Among 1144 hemispheres, 24 were considered posterior auricular artery-EDAS candidates (2.1%). Of those, 10 hemispheres underwent posterior auricular artery-EDAS (41.7%, in total hemispheres 0.9%). Comparing the Matsushima grades of the superficial temporal artery-EDAS and posterior auricular artery-EDAS groups showed similar postoperative revascularization. Postoperative Karnofsky Performance Scale and mRS scores of patients having undergone posterior auricular artery-EDAS did not show deterioration. CONCLUSIONS: In approximately 2% of pediatric patients with Moyamoya disease for whom the superficial temporal artery is unavailable as the EDAS donor, the posterior auricular artery can be considered an alternative. On the basis of the results, the clinical outcome of posterior auricular artery-EDAS was not inferior to that of superficial temporal artery-EDAS. Hence, we suggest an in-depth consideration of the posterior auricular artery as the donor artery if the superficial temporal artery parietal branch is unavailable.


Asunto(s)
Enfermedad de Moyamoya , Adolescente , Variación Anatómica , Angiografía Cerebral , Revascularización Cerebral , Niño , Preescolar , Femenino , Humanos , Masculino , Enfermedad de Moyamoya/diagnóstico por imagen , Enfermedad de Moyamoya/cirugía , Estudios Retrospectivos , Arterias Temporales/diagnóstico por imagen , Arterias Temporales/cirugía , Resultado del Tratamiento
8.
Osteoporos Int ; 32(6): 1071-1078, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33411009

RESUMEN

The association of BMI with falls differed between men and women in Korea. Obesity was associated with a greater risk of falls in women, whereas underweight seemed to increase the risk of falls compared with normal weight in men. PURPOSE: This study examined the sex-specific association between body mass index (BMI) and falls in Korean adults using data from a large population-based survey. METHODS: We analyzed 113,805 men and women (age ≥ 50 years) who participated in the Korean Community Health Survey in 2013. Logistic regression was used to assess the relationship between BMI and falls. RESULTS: The mean (± standard deviation) age and BMI of all participants were 63.8 ± 9.6 years and 23.2 ± 2.9 kg/m2, respectively. Among the 113,805 subjects, 19.1% and 6.7% had histories of falls and recurrent falls, respectively. The association of BMI with recurrent falls differed between men and women. The multivariable-adjusted odd ratios (ORs) for recurrent falls were 0.98 (95% confidence interval [CI] 0.86-1.12), 1.23 (1.14-1.32), and 1.51 (1.26-1.81) in women with BMIs of < 18.5, 25-29.9, and ≥ 30 kg/m2, respectively, relative to those with BMIs of 18.5-24.9 kg/m2. The corresponding ORs for men were 1.20 (95% CI 1.01-1.42), 1.05 (0.96-1.14), and 0.97 (0.69-1.38), respectively. Older age and low economic level were associated independently with higher ORs of recurrent falls in men and women, respectively. In addition, comorbidities, including diabetes, stroke, arthritis, osteoporosis, and asthma, correlated significantly with an increased risk of recurrent falls (all p < 0.001). CONCLUSIONS: Obesity was associated with a greater risk of recurrent falls in women, whereas underweight seemed to be associated with a greater risk of falls in men.


Asunto(s)
Delgadez , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Factores de Riesgo
9.
Rhinology ; 59(3): 292-300, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33315021

RESUMEN

BACKGROUND: Chronic rhinosinusitis (CRS) and chronic otitis media (COM) share pathophysiological mechanisms such as bacterial infection, biofilm, and persistence of the obstruction state of ventilation routes. However, only a few studies have investigated the relationship between these two diseases nationwide and in the general population. The purpose of this study was to determine whether the incidence of COM in patients with CRS differed from that of a matched control from the national health screening cohort. METHODS: Data from the Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2015. Participants who were treated ≥ ≥ ≥2 times and underwent head and neck computed tomography evaluation were selected. A 1:4 matched CRS group (n=8,057) and a control group (n=32,228) were selected. The control group included participants who were never treated with the ICD-10 code J32 from 2002 to 2015. The CRS group included CRS patients with/without nasal polyps. RESULTS: The incidence of COM was significantly higher in the CRS group than in the control group. In a subgroup analysis, the incidence of COM in all age groups and in men and women was significantly higher in the CRS group than in the control group. More, CRS increased the risk of COM. CONCLUSIONS: A significant association was observed between CRS and COM. This indicates that CRS patients have a high risk of developing COM.


Asunto(s)
Pólipos Nasales , Otitis Media , Rinitis , Sinusitis , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Otitis Media/complicaciones , Otitis Media/epidemiología , Rinitis/epidemiología , Sinusitis/epidemiología
10.
Clin Transl Oncol ; 23(3): 459-467, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32617871

RESUMEN

PURPOSE: This study investigated the degree of tumor cell infiltration in the tumor cavity and ventricle wall based on fluorescent signals of 5-aminolevulinic acid (5-ALA) after removal of the magnetic resonance (MR)-enhancing area and analyzed its prognostic significance in glioblastoma. METHODS: Twenty-five newly developed isocitrate dehydrogenase (IDH)-wildtype glioblastomas with complete resection both of MR-enhancing lesions and strong purple fluorescence on resection cavity were retrospectively analyzed. The fluorescent signals of 5-ALA were divided into strong purple, vague pink, and blue colors. The pathologic findings were classified into massively infiltrating tumor cells, infiltrating tumor cells, suspicious single-cell infiltration, and normal-appearing cells. The pathological findings were analyzed according to the fluorescent signals in the resection cavity and ventricle wall. RESULTS: There was no correlation between fluorescent signals and infiltrating tumor cells in the resection cavity (p = 0.199) and ventricle wall (p = 0.704) after resection of the MR-enhancing lesion. The median progression-free survival (PFS) and median overall survival (OS) were 12.5 (± 2.1) and 21.1 (± 3.5) months, respectively. In univariate analysis, the presence of definitive infiltrating tumor cells in the resection cavity and ventricle wall was significantly related to the PFS (p = 0.002) and OS (p = 0.027). In multivariate analysis, the absence of definitive infiltrating tumor cells improved PFS (hazard ratio: 0.184; 95% CI: 0.049-0.690, p = 0.012) and OS (hazard ratio: 0.124; 95% CI: 0.015-0.998, p = 0.050). CONCLUSIONS: After resection both of the MR-enhancing lesions and strong purple fluorescence on resection cavity, there was no correlation between remnant fluorescent signals and infiltrating tumor cells. The remnant definitive infiltrating tumor cells in the resection cavity and ventricle wall significantly influenced the prognosis of patients with glioblastoma. Aggressive surgical removal of infiltrating tumor cells may improve their prognosis.


Asunto(s)
Ácido Aminolevulínico/metabolismo , Neoplasias Encefálicas/patología , Movimiento Celular , Glioblastoma/patología , Isocitrato Deshidrogenasa , Fármacos Fotosensibilizantes/metabolismo , Anciano , Ácido Aminolevulínico/administración & dosificación , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/cirugía , Ventrículos Cerebrales/metabolismo , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Femenino , Fluorescencia , Glioblastoma/metabolismo , Glioblastoma/mortalidad , Glioblastoma/cirugía , Humanos , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fármacos Fotosensibilizantes/administración & dosificación , Pronóstico , Supervivencia sin Progresión , Protoporfirinas/metabolismo , Estudios Retrospectivos , Proteínas Supresoras de Tumor/genética
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