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1.
J Phys Chem Lett ; 15(35): 8924-8932, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39172703

RESUMEN

We investigated the phonon behavior of ZnO-buffered MgB2 tapes with varying ZnO buffer layer thicknesses using polarized Raman spectroscopy at room and cryogenic temperatures. Polar plots from integrated angle-resolved polarized Raman spectroscopy (ARPRS) at room temperature revealed substantial distortion in the boron plane geometry due to lattice mismatch among the MgB2 film, ZnO buffer layer, and Hastelloy substrate. This distortion significantly affects the electron-phonon coupling (EPC) constant, λ, which we calculated using the modified McMillan equation by Allen-Dynes in relation to the superconducting transition temperature (Tc) of the sample. At cryogenic temperatures, our investigation of the E2g mode exhibited a notable phonon hardening effect of up to ∼4.1%, correlated with the ZnO buffer layer thickness. Furthermore, analysis of the anharmonic E2g phonon mechanism through line width (full width at half maximum) revealed damping behavior, indicating an additional coupling mechanism within the sample that varies with the temperature. This unique Raman scattering behavior potentially elucidates the high Tc mechanism of MgB2, which is underestimated by traditional EPC calculations. Additionally, increasing the thickness of the ZnO layer is predicted to alleviate the distortion in the boron plane geometry, thereby promoting MgB2 toward its inherent electron-phonon superconducting nature by mitigating the additional coupling mechanisms. Understanding how the ZnO buffer layer influences the phonon dynamics and EPC in MgB2 will provide critical insights into optimizing its superconducting properties and advancing its practical applications in high-performance superconducting devices.

2.
Int J Tuberc Lung Dis ; 28(2): 73-80, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38303039

RESUMEN

BACKGROUND: The importance of early intravenous (IV) antibiotic use for Mycobacterium abscessus complex lung diseases (MABC-LD) treatment remains unknown. METHODS: A retrospective multi-centre observational study was conducted in Taiwan. Patients who were diagnosed with and received treatment for MABC-LD from January 2007 to April 2021 were included. Treatment outcome was defined as modified microbiological cure of MABC-LD.RESULTS: Of the 89 enrolled patients, 34 (38.2%) received IV antibiotics as part of the treatment regimen. The median time to IV initiation was 1 day (IQR 1???49); 24 (70.6%) of these patients received IV agents within 4 weeks, defined as early-use. Forty-two (47.2%) patients achieved modified microbiological cure. In the multivariable logistic analysis, early IV antibiotic use was an independent factor associated with modified microbiological cure (aOR 5.32, 95% CI 1.66???17.00), whereas high radiological score (aOR 0.86, 95% CI 0.73???1.00) demonstrated negative association.CONCLUSIONS: In the present study, early use of effective IV antibiotic was prescribed in a low percentage (27%) for MABC-LD. By contrast, early IV antibiotic use was correlated with higher microbiological cure than were late or non-use. Future larger and prospective studies are needed to validate the association.


Asunto(s)
Enfermedades Pulmonares , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Humanos , Antibacterianos/uso terapéutico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/microbiología , Estudios Prospectivos , Estudios Retrospectivos
3.
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.

4.
Public Health ; 221: 208-215, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37490839

RESUMEN

OBJECTIVES: North Korean Refugees (NKRs) undergo defection, and this has been shown to impact their current health status in South Korea. However, little is understood about how the defection process is related to metabolic syndrome (MetS). This study regarded the defection process to be a quasi-measurement of traumatic experience and investigated whether defection was a risk factor for MetS among NKRs living in South Korea. STUDY DESIGN: This cross-sectional study obtained data from the Korea University Anam Hospital in Seoul. NKRs (N = 847) voluntarily completed questionnaires and underwent at least one medical examination between October 2008 and July 2021. METHODS: Multivariable logistic regression models were used to evaluate whether the number of countries transited by NKRs was associated with MetS by controlling for covariates. RESULTS: The prevalence of MetS among male and female NKRs in South Korea was 12.3% and 13.3%, respectively. The highest prevalence of MetS (33.4%) was among NKRs who had transited two countries. The number of months in transit countries (mean: 49.9 ± 51.7) and period of residence in South Korea (mean: 40.9 ± 40.9 months) were also considered. NKRs who transited three countries had a higher probability of MetS (odds ratio [OR] 2.660, 95% confidence interval [CI] 1.161-6.097) than those who travelled directly to South Korea. NKRs who transited three countries and had only resided in South Korea for a short period had a higher probability of MetS (OR 3.424, 95% CI 1.149-10.208) than those who have lived in South Korea for a longer period. CONCLUSIONS: Considering the social vulnerability of NKRs and consequential health problems, there is an urgent need for appropriate support from the government and society.


Asunto(s)
Síndrome Metabólico , Refugiados , Humanos , Masculino , Femenino , Síndrome Metabólico/epidemiología , República Popular Democrática de Corea/epidemiología , Estudios Transversales , República de Corea/epidemiología , Libertad
5.
Anaesthesia ; 78(8): 988-994, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36960477

RESUMEN

We aimed to investigate the effect of the analgesia nociception index on postoperative pain. We randomly allocated 170 women scheduled for gynaecological laparotomy and analysed results from 159: in 80 women, remifentanil was infused to maintain analgesia nociception indices 50-70; and in 79 women, remifentanil was infused to maintain systolic blood pressure < 120% of baseline values. The primary outcome was the proportion of women with pain scores ≥ 5 (scale 0-10) within 40 min of admission to recovery. The proportion of women with pain scores ≥ 5 was 62/80 (78%) vs. 64/79 (81%), p = 0.73. Mean (SD) doses of fentanyl in recovery were 53.6 (26.9) µg vs. 54.8 (20.8) µg, p = 0.74. Intra-operative remifentanil doses were 0.124 (0.050) µg.kg-1 .min-1 vs. 0.129 (0.044) µg.kg-1 .min-1 , p = 0.55.


Asunto(s)
Analgesia , Analgésicos Opioides , Humanos , Femenino , Remifentanilo , Nocicepción , Laparotomía , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control
7.
Eur J Paediatr Dent ; 23(2): 101-105, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35722843

RESUMEN

AIM: To evaluate the relationship between dental calcification and skeletal maturity and to identify the tooth with the highest correlation with skeletal maturity index in Korean children. MATERIALS: For 447 children (205 boys and 242 girls) aged between 5 and 13 years, hand-wrist and lateral cephalometric radiographs were taken to assess skeletal maturity by Fishman's skeletal maturity indicators (SMI) and Baccetti's cervical vertebrae maturation (CVM) stages. Dental panoramic radiographs were taken to assess dental maturity of the permanent mandibular canine, first and second premolar, and second molar using the method devised by Dermirjian. CONCLUSION: Dental calcification stages determined by panoramic radiographs can be clinically used as useful indices to predict skeletal maturity in Korean children.


Asunto(s)
Determinación de la Edad por el Esqueleto , Calcificación de Dientes , Determinación de la Edad por el Esqueleto/métodos , Diente Premolar , Vértebras Cervicales/diagnóstico por imagen , Humanos , Radiografía Panorámica/métodos , República de Corea
8.
Neurochirurgie ; 68(6): e97-e100, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35314067

RESUMEN

Hypertrophic pachymeningitis can lead to clinical brainstem and cervical spinal cord compression leading to neurologic deficits. IgG4-related hypertrophic pachymeningitis (IgG4-RHP) is one recently recognized etiology of previously idiopathic cases. A 34-year-old right-handed female presented with slowly progressive neurologic symptoms and worsening radiographic syringomyelia. She successfully underwent Chiari decompression and excision of her pachymeningitis with improvement in her radiographic findings. Extensive clinical workup has led to a diagnosis of IgG4-RHP and treatment with steroids. IgG4-RHP is a rare cause of spinal cord compression and on our review of the literature this is the first description of significant syringomyelia associated with this condition. This remains a challenging entity to treat and neurology and rheumatology referrals should be placed early to investigate IgG4-RHP as an etiology for idiopathic cases. Treatment of this disease is likely to evolve with further research.


Asunto(s)
Meningitis , Compresión de la Médula Espinal , Siringomielia , Humanos , Femenino , Adulto , Compresión de la Médula Espinal/etiología , Compresión de la Médula Espinal/cirugía , Siringomielia/complicaciones , Siringomielia/cirugía , Inmunoglobulina G , Meningitis/complicaciones , Meningitis/diagnóstico , Meningitis/cirugía , Hipertrofia/cirugía , Hipertrofia/complicaciones , Descompresión , Imagen por Resonancia Magnética
10.
BJOG ; 128(12): 1938-1948, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34028167

RESUMEN

OBJECTIVE: To quantify familial risk of endometriosis among full siblings and examine interactions between family history and smoking, age at menarche or body mass index (BMI). DESIGN, SETTING AND POPULATION: Population-based nationwide cohort study. METHODS: Using data from the Korean National Health Insurance and Screening Programme databases on kinship, healthcare utilisation, lifestyle and anthropometrics, we identified 2 109 288 women with full siblings and their environmental risk factors from 2002 to 2018. Familial risks were estimated using Cox proportional-hazards models, represented as incidence risk ratios (IRR) with 95% CI. Interaction between family history and smoking, age at menarche or BMI were assessed on an additive scale. MAIN OUTCOME MEASURES: IRR of endometriosis among women with and without affected siblings. RESULTS: From 19 195 women with affected siblings, 1126 developed endometriosis with an incidence of 35.45/10 000 person-years. Familial risk of endometriosis with versus without affected siblings was increased to IRR 2.75 (95% CI 2.25-3.36), and the highest risk was with affected twins (IRR 6.98; 95% CI 4.19-11.62). Women with both a family history and either smoking, early menarche or low BMI had a significantly higher risk of endometriosis compared with the general population and can be regarded as a high-risk group, the IRRs were 4.28 (95% CI 2.43-7.55), 3.47 (95% CI 2.82-4.26) and 3.09 (95% CI 2.68-3.56), respectively. Substantial effect modification of the associations was noted by smoking and early menarche, as their combined risk with family history exceeded the sum of their individual risks, which was also statistically significant. CONCLUSION: Genetic factors are the primary contributor to the familial aggregation of endometriosis. Significant gene-environment interaction exists between family history and smoking or early menarche. TWEETABLE ABSTRACT: Significant gene-environment interaction exists between family history of endometriosis and smoking or early menarche.


Asunto(s)
Susceptibilidad a Enfermedades/epidemiología , Susceptibilidad a Enfermedades/etiología , Endometriosis/epidemiología , Endometriosis/etiología , Hermanos , Adolescente , Adulto , Factores de Edad , Índice de Masa Corporal , Femenino , Interacción Gen-Ambiente , Humanos , Incidencia , Menarquia , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , República de Corea/epidemiología , Factores de Riesgo , Fumar/efectos adversos , Fumar/epidemiología , Adulto Joven
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