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1.
Appl Opt ; 60(24): 7152-7157, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34613001

RESUMEN

Device-to-device (D2D) communication that delivers a dedicated channel with low latency and high spectral efficiency has been considered an essential solution for vehicle-to-vehicle (V2V) communication. To achieve such D2D-V2V communication, the beam-steering technique using optical wavelengths can be an attractive candidate due to the advanced optical wireless technologies for point-to-point applications. Recently, there has been research on high-performance optical beam-steering techniques based on microelectromechanical systems mirrors and spatial light modulators in quasi-static indoor environments. Due to the optomechanical complexity, size, and cost, however, their suitability for D2D-V2V applications is problematic. In this work, a cost-effective optical beam-steering system based on a fluorescent reflector and stereo vision for D2D-V2V is introduced. Proof-of-concept demonstration using off-the-shelf devices and components shows that the proposed system can support +-30-deg field of view with a data rate of 300 Mb/s.

2.
J Synchrotron Radiat ; 26(Pt 4): 1127-1138, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31274436

RESUMEN

PAL-XFEL utilizes a three-chicane bunch compression (3-BC) scheme (the very first of its kind in operation) for free-electron laser (FEL) operation. The addition of a third bunch compressor allows for more effective mitigation of coherent synchrotron radiation during bunch compression and an increased flexibility of system configuration. Start-to-end simulations of the effects of radiofrequency jitter on the electron beam performance show that using the 3-BC scheme leads to better performance compared with the two-chicane bunch compression scheme. Together with the high performance of the linac radiofrequency system, it enables reliable operation of PAL-XFEL with unprecedented stability in terms of arrival timing, pointing and intensity; an arrival timing jitter of better than 15 fs, a transverse position jitter of smaller than 10% of the photon beam size, and an FEL intensity jitter of smaller than 5% are consistently achieved.

3.
Asian Pac J Allergy Immunol ; 35(2): 96-101, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27543733

RESUMEN

BACKGROUND: Prevalence of anaphylaxis is increasing steadily, but there is scant information about anaphylaxis. OBJECTIVE: To identify the prevalence of anaphylaxis and evaluate the cause and features of anaphylaxis according to age. METHOD: The relevance of gender, age, history of allergic diseases, causes and clinical symptoms in the treatment and prognosis of anaphylaxis were retrospectively evaluated in patients diagnosed with anaphylaxis in Pusan National University Hospital from January 2009 to June 2014. RESULTS: The 161 patients included 30 children and 131 adults. The prevalence of anaphylaxis in both children and adults increased during the study period. The most common triggers were food in children, especially in those <5 years of age, and drugs in adults. All of the children with episodes of anaphylaxis presented with cutaneous symptoms and 90% had respiratory symptoms. For adults, cardiovascular symptoms were more common. CONCLUSIONS: The prevalence of anaphylaxis increased in both children and adults, with a higher rate in children. The causes and symptoms of anaphylaxis may differ depending on age. Clinicians should understand the characteristics of anaphylaxis by age.


Asunto(s)
Anafilaxia/diagnóstico , Anafilaxia/epidemiología , Hospitales Universitarios/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , República de Corea/epidemiología , Estudios Retrospectivos , Distribución por Sexo
4.
Sci Rep ; 13(1): 4484, 2023 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-36934136

RESUMEN

We retrospectively analyzed National Health Insurance claims data (January 2002-December 2018) to determine the asthma prevalence and risk factors among preterm infants born in Korea. Patients with asthma were defined as those with a history of asthma medication prescriptions at least twice per year with International Classification of Diseases, Tenth Edition codes J45 and J46. We enrolled 99,139 preterm infants. The prevalence of asthma among preterm and term infants was 32.7% and 26.9%, 21.2% and 19.1%, 6.7% and 5.9%, 2.0%, and 1.6%, and 2.4% and 1.6% at 2, 5, 10, 15, and 16 years of age, respectively. The relative risk (RR) of asthma in preterm infants was 1.1-fold that in female preterm infants. The RR of asthma medication prescriptions for infants with extreme prematurity was 1.92-fold that of infants with moderate/late pre-term status. Among preterm with bronchopulmonary dysplasia (BPD) and respiratory distress syndrome (RDS) without comorbidities, the RRs for the number of asthma medication prescriptions were 1.34 and 1.06, respectively. This study revealed a higher prevalence of asthma among preterm infants than that in term infants. Male sex, extreme prematurity, BPD, and RDS were identified as risk factors for asthma medication prescriptions in preterm infants.


Asunto(s)
Asma , Displasia Broncopulmonar , Síndrome de Dificultad Respiratoria del Recién Nacido , Lactante , Recién Nacido , Humanos , Masculino , Femenino , Recien Nacido Prematuro , Prevalencia , Estudios Retrospectivos , Asma/tratamiento farmacológico , Asma/epidemiología , Asma/etiología , Factores de Riesgo , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Prescripciones de Medicamentos , Displasia Broncopulmonar/epidemiología , República de Corea/epidemiología
5.
Clin Anat ; 21(1): 33-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18038453

RESUMEN

The authors measured the diameters of vessels around the surgical plane of tonsillectomy to investigate an anatomical basis to reduce hemorrhage. Thirty tonsils removed from 15 adult cadavers with the mean age of 56 years (range 44-71 years) at the time of death were studied. Calibration of the vessels across the tonsillar capsule was performed at the 1-mm intracapsular, capsular, and 1-mm extracapsular plane as artery and vein, respectively. The average diameter of the arteries was 73.0 +/- 33.1 mum at the 1-mm intracapsular plane, 94.7 +/- 33.5 mum at the capsular plane, and 139.5 +/- 51.2 mum at the 1-mm extracapsular plane. For the veins, it was 62.9 +/- 38.7 mum at the 1-mm intracapsular plane, 86.8 +/- 50.4 mum at the capsular plane, and 133.6 +/- 78.6 mum at the 1-mm extracapsular plane. The diameters of the vessels at the 1-mm intracapsular plane were significantly smaller than those at the capsular plane (P < 0.01), and likewise the diameters of the vessels at the capsular plane were significantly smaller than those at the 1-mm extracapsular plane (P < 0.01). The result of this study on the diameter of the vessels across the tonsillar capsule could be considered to be an important factor providing an anatomical rationale for a change in recommendation leading to safer tonsillectomies that minimize vascular injury.


Asunto(s)
Arterias/anatomía & histología , Tonsila Palatina/irrigación sanguínea , Tonsilectomía/métodos , Venas/anatomía & histología , Adulto , Anciano , Femenino , Humanos , Complicaciones Intraoperatorias/prevención & control , Masculino , Persona de Mediana Edad , Hemorragia Posoperatoria/prevención & control , Tonsilectomía/efectos adversos
6.
J Microbiol ; 44(5): 523-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17082746

RESUMEN

OSH3 is one of the seven yeast homologues of the oxysterol binding proteins (OSBPs) which have the major binding affinity to the oxysterols and function as regulator of cholesterol biosynthesis in mammals. Mutational analysis of OSH3 showed that OSH3 plays a regulatory role in the yeast-to-hyphal transition through its oxysterol-binding domain in Saccharomyces cerevisiae. The OSH3 gene was also identified in the pathogenic yeast Candida albicans. Deletion of OSH3 caused a defect in the filamentous growth, which is the major cause of the C. albicans pathogencity. The filamentation defect of the mutation in the MAPK-associated transcription factor, namely cph1Delta was suppressed by overexpression of OSH3. These findings suggest the regulatory roles of OSH3 in the yeast filamentous growth and the functional conservations of OSH3 in S. cerevisiae and C. albicans.


Asunto(s)
Candida albicans/genética , Receptores de Esteroides/genética , Saccharomyces cerevisiae/genética , Candida albicans/crecimiento & desarrollo , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiología , Eliminación de Gen , Regulación Fúngica de la Expresión Génica/genética , Modelos Genéticos , Fenotipo , Reacción en Cadena de la Polimerasa/métodos , Receptores de Esteroides/fisiología , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/fisiología , Factores de Transcripción/genética
7.
J Forensic Sci ; 51(5): 979-84, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17018072

RESUMEN

The identification of unknown remains is very important. When unknown remains are found, anthropologists first determine their sex and age. The sex of most skeletons is determined by their shape. In the hyoid bone, the shape is sex related, so it can be used forensically to determine the sex. This study focused on sex-based morphometry of the hyoid bone in Koreans using digital photographs. Hyoid bones from 52 males and 33 females were examined. For each subject, we took 34 measurements from photographs using a computer program, and the data were analyzed statistically using SPSS 11.0. Twenty-one of 34 measurements had significant sex differences (p<0.05). The discriminant functions based on three measurements (X(1)-X(3)) were as follows: The accuracy of discriminant functions is 88.2% in both groups, so these can be used to distinguish males from females in a statistically significant manner.


Asunto(s)
Antropología Forense , Hueso Hioides/anatomía & histología , Caracteres Sexuales , Adulto , Anciano , Análisis Discriminante , Femenino , Humanos , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Fotograbar
8.
Allergy Asthma Immunol Res ; 8(2): 156-60, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26739409

RESUMEN

PURPOSE: The purpose of this study was to establish the diagnostic decision point (DDP) of peanut specific IgE (sIgE) for predicting the outcome of oral food challenge (OFC). We also evaluated the usefulness of sIgE to peanut components (Ara h 1, 2, 3, 8, and 9) in diagnosing peanut allergy. METHODS: Korean children aged over 12 months with a suspected peanut allergy were enrolled. Diagnosis of peanut allergy was confirmed by an open OFC or through the convincing history of anaphylaxis. Cutoff levels of sIgE to peanut and peanut components were determined by analyzing receiver operating characteristic curves. RESULTS: Forty-eight children (22 boys and 26 girls) with a suspected peanut allergy were enrolled. The previously established DDP for peanut-sIgE antibodies (14 kU/L) showed a sensitivity of 22.7%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value of 60.4% in our study population. The median levels of peanut-sIgE (5.4 kU/L vs 1.1 kU/L, P<0.001) and Ara h 2-sIgE (0.8 kU/L vs 0 kU/L, P<0.001) were significantly higher in the peanut allergy group than in the peanut tolerance group. The peanut-sIgE concentration indicating a PPV of 100% was 10.3 kU/L. The Ara h 2-sIgE level of 4.0 kU/L had a PPV of 100%. CONCLUSIONS: Our results showed that the cutoff levels for peanut (10.3 kU/L) and Ara h 2 (4.0 kU/L) established in this study is useful for the diagnosis of peanut allergy in Korean children.

9.
Forensic Sci Int ; 148(2-3): 225-31, 2005 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-15639619

RESUMEN

In this study, 12 Y-specific STR loci--DYS391, DYS389 I, DYS439, DYS389 II, DYS438, DYS437, DYS19, DYS392, DYS393, DYS390, DYS385a/b--were analyzed in 259 unrelated males from the southern populations in Korea using the PowerPlex Y PCR system.


Asunto(s)
Cromosomas Humanos Y , Frecuencia de los Genes , Genética de Población , Haplotipos , Secuencias Repetidas en Tándem , Dermatoglifia del ADN/métodos , Humanos , Corea (Geográfico) , Masculino , Reacción en Cadena de la Polimerasa/métodos
10.
Biointerphases ; 10(2): 021004, 2015 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-25924607

RESUMEN

The present study evaluated the tribological properties of the articular cartilage surface of the human femoral head with postcollapse stage avascular necrosis (AVN) using atomic force microscopy. The cartilage surface in the postcollapse stage AVN of the femoral head was reported to resemble those of disuse conditions, which suggests that the damage could be reversible and offers the possibilities of success of head-sparing surgeries. By comparing the tribological properties of articular cartilage in AVN with that of osteoarthritis, the authors intended to understand the cartilage degeneration mechanism and reversibility of AVN. Human femoral heads with AVN were explanted from the hip replacement surgery of four patients (60-83 years old). Nine cylindrical cartilage samples (diameter, 5 mm and height, 0.5 mm) were sectioned from the weight-bearing areas of the femoral head with AVN, and the cartilage surface was classified according to the Outerbridge Classification System (AVN0, normal; AVN1, softening and swelling; and AVN2, partial thickness defect and fissuring). Tribological properties including surface roughness and frictional coefficients and histochemistry including Safranin O and lubricin staining were compared among the three groups. The mean surface roughness Rq values of AVN cartilage increased significantly with increasing Outerbridge stages: Rq = 137 ± 26 nm in AVN0, Rq = 274 ± 49 nm in AVN1, and Rq = 452 ± 77 nm in AVN2. Significant differences in Rq were observed among different Outerbridge stages in all cases (p < 0.0001). The frictional coefficients (µ) also increased with increasing Outerbridge stages. The frictional coefficient values were µ = 0.115 ± 0.034 in AVN0, µ = 0.143 ± 0.025 in AVN1, and µ = 0.171 ± 0.039 in AVN2. Similarly to the statistical analysis of surface roughness, significant statistical differences were detected between different Outerbridge stages in all cases (p < 0.05). Both surface roughness and frictional coefficient of cartilage, which were linearly correlated, increased with increasing Outerbridge stages in postcollapse AVN. The underlying mechanism of these results can be related to proteoglycan loss within the articular cartilage that is also observed in osteoarthritis. With regard to the tribological properties, the cartilage degeneration mechanism in AVN was similar to that of osteoarthritis without reversibility.


Asunto(s)
Cartílago Articular/patología , Necrosis de la Cabeza Femoral/patología , Fémur/patología , Propiedades de Superficie , Anciano , Anciano de 80 o más Años , Histocitoquímica , Humanos , Microscopía , Microscopía de Fuerza Atómica , Persona de Mediana Edad
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