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The synthetic aperture radar(SAR) is an equipment that can acquire images in all weathers day and night based on radar signals. The on-board processor of satellite SAR generates transmission signal by digital signal processing, converts it into an analog signal and transmits to antenna. Until the transmission signal generated by on-board processor is output, the signal passes the transmission cables and analog devices. At this time, these hardware distort the signal and makes SAR performance worse. To improve the performance, pre-distortion technique is used. But, general pre-distortion using taylor series is not sufficient to compensate for the distortion. This paper suggests transmit signal design method with improved pre-distortion. This paper uses envelop sampling method and interpolation filter for frequency domain compensation. The proposed method accurately compensates the hardware distortion and reduces resource usage of FPGA. To analyze proposed method’s performance, IRF characteristics are compared when the proposed method applies to signal with errors.

The on-board processor of satellite synthetic aperture radar(SAR) generates transmission signal by digital signal processing, converts it into an analog signal. At this time, the transmission signal generated from the baseband requires the frequency modulation to convert it to the high-frequency band in order to improve the stability. General frequency modulation method using local oscillator(LO) causes IQ imbalance due to phase error/magnitude error and these error reduce performance of SAR. To generate transmission signal without phase/magnitude error, this paper suggests design method of the frequency modulation method using digital to analog converter(DAC) at on-board SAR. For design, this paper analyzes the characteristic of DAC mode and uses pre-compensation filter. To analyze the proposed method performance, performance index are compared with IQ imbalance signals. This method is suitable for on-board SAR using fast sampling DAC and has the advantage of being able to solve IQ imbalances.

This study introduces a facile method for synthesizing covalently bonded magnetic carbon nanoparticles (MCNs) in which carboxylic acid-functionalized activated carbon nanospheres (ACN-COOH) are connected with amine-terminated iron oxide nanoparticles (NPs) (Fe3O4-NH2) via a carbodiimide crosslinking reaction. The adsorption characteristics of the developed magnetic nanoparticles (ACN-Fe3O4) were investigated using a standard cationic dye (methylene blue, MB). Two additional MCNs (multi-core and core@shell structures) were also prepared, and their adsorption performances were extensively compared. The developed ACN-Fe3O4 material thoroughly utilizes the strengths of activated carbon and Fe3O4 themselves, exhibiting large specific surface areas (708.4 m2/g) and strong magnetic properties (40.3 emu/g), resulting in high adsorption capacity (349.5 mg/g) and recycling efficiency (76 % of adsorption performance after four cycles). In addition, a study of the mechanism reveals that pore-filling processes are dominant with minor contributions from electrostatic interactions, π–π interactions, and n–π interactions. The developed covalently bonded magnetic carbon nanoparticles (ACN-Fe3O4) can thus be considered as competent adsorbents with the potential to compensate for the drawbacks of contemporary MCNs, such as, low adsorption capacity, and weak magnetic properties.

Silicon particles have garnered attention as promising biomedical probes for hyperpolarized 29Si magnetic resonance imaging and spectroscopy. However, due to the limited levels of hyperpolarization for nanosized silicon particles, microscale silicon particles have primarily been the focus of dynamic nuclear polarization (DNP) applications, including in vivo magnetic resonance imaging (MRI). To address these current challenges, we developed a facile synthetic method for partially 29Si-enriched porous silicon nanoparticles (NPs) (160 nm) and examined their usability in hyperpolarized 29Si MRI agents with enhanced signals in spectroscopy and imaging. Hyperpolarization characteristics, such as the build-up constant, the depolarization time (T1), and the overall enhancement of the 29Si-enriched silicon NPs (10 and 15%), were thoroughly investigated and compared with those of a naturally abundant NP (4.7%). During optimal DNP conditions, the 15% enriched silicon NPs showed more than 16-fold higher enhancements─far beyond the enrichment ratio─than the naturally abundant sample, further improving the signal-to-noise ratio in in vivo29Si MRI. The 29Si-enriched porous silicon NPs used in this work are potentially capable to serve as drug-delivery vehicles in addition to hyperpolarized 29Si in vivo, further enabling their potential future applicability as a theragnostic platform.

The on-board processor of satellite Synthetic Aperture Radar(SAR) digitizes the back-scattered echoes and transmits them to the ground. As satellite SAR image of various operating conditions including broadband and high resolution is required, an enormous amount of SAR data is generated. Decimation filter is used for data compression to improve the transmission efficiency of these data. Decimation filter is implemented with the FIR(Finite Impulse Response) filter and here, the decimation ratio and tap length are constrained by resource requirements of FPGA used for implementation. This paper suggests to use a non-integer ratio decimation filter in order to optimize the data transmission efficiency. Also, it proposes a filter design method that remarkably reduces the resource constraints of the FPGA in-use via applying a polyphase filter structure. The required resources for implementing the proposed filter is analysed in this paper.

Background Background: Hot springs have been traditionally used as an alternative treatment for a wide range of diseases, including rheumatoid arthritis, bronchial asthma, diabetes, hypertension, psoriasis and atopic dermatitis. However, the clinical effects and therapeutic mechanisms associated with hot springs remain poorly defined. Objective The purpose of this study was to demonstrate the different effects of hot springs on cellular viability and secretion of inflammatory cytokines on keratinocyte in two geographically representative types of hot springs: NaHCO3-type and NaCl-type, which are the most common types in South Korea. Methods We performed WST-1, BrdU measurements, human inflammatory cytokine arrays and enzyme-linked immunosorbent assay in HaCaT cells stimulated with toll-like receptor 3 by polyinosinicpolycytidylic acid. Results The interaction effects of cell viability and cell proliferation were not significantly different regardless of polyinosinic-polycytidylic acid stimulation and cultured hot springs type. Cytokine array and enzymelinked immunosorbent assay analysis showed increased expression of inflammatory cytokines such as interleukin6 and granulocyte-macrophage colony-stimulating factor by polyinosinic-polycytidylic acid stimulation, with expression levels differing according to hot springs hydrochemical composition. Cytokine reduction was not significant. Conclusion The effects and mechanisms of hot springs treatment in keratinocytes were partially elucidated.

Metabolic syndrome (MetS) is characterized by insulin resistance, high blood pressure/sugar, dyslipidemia, and obesity. Whether MetS and its components affect the development of Behçet's disease (BD) remains unclear. This study was performed to investigate the associations between metabolic syndrome and risk of BD using nationwide population data. We conducted a retrospective cohort study of 10 505 818 Korean subjects who received health checkups in 2009-2012. Patients were classified into a MetS and its components group and were followed-up until 2016 for new-onset BD. A Cox proportional hazards model was used to assess the independent or synergistic effects of MetS and its components on the risk of incident BD. Compared to subjects without MetS components, the hazard ratio (HR) for development of BD in patients with MetS was 0.874 (95% confidence interval [CI]: 0.819-0.933) and this association was more prominent when all components of MetS were present (HR = 0.675, 95% CI = 0.571-0.798). Subjects with low high density lipoprotein (HDL) has a significantly increased risk of the development of BD (HR = 1.51, 95% CI = 1.4-1.594) compared to controls. This study showed that the incidence of Behçet's disease was reduced in subjects with MetS. Moreover, the presence of MetS components, with the exception of HDL, was negatively related to the development of BD.

Background: No epidemiologic study has previously reported on the associations among Behçet’s disease (BD) and autoimmune disorders. Objectives: To investigate the association between BD and the autoimmune disorders multiple sclerosis and rheumatoid arthritis. Methods: Medical records of patients newly diagnosed with BD (n = 6,214) in 2012–2017 were analyzed using data entered into a large, nationwide database from 2007 to 2017. An age- and sex-matched control population of individuals without BD was sampled at a ratio of controls:BD cases of 3:1 (n = 18,642). Both cohorts were analyzed for the presence of multiple sclerosis or rheumatoid arthritis within a minimum of 5 years prior to their BD diagnosis. Results: Patients with BD had significantly higher odds ratios (ORs) for multiple sclerosis (8.85 [95% CI 2.36–33.17]) and rheumatoid arthritis (4.62 [95% CI 3.35–6.35]) than the control group after adjustment for diabetes mellitus, hypertension, and dyslipidemia. BD patients aged Conclusion: Our results suggest that BD is associated with multiple sclerosis and rheumatoid arthritis.

This study introduces a robust synthetic method of fabricating co-assembled biodegradable microcapsules composed mainly of representative natural sugar polymers, hydroxyethylcellulose (HEC), alginate, and sorbitol. We propose a facile enzymatic method evaluating initial biodegradation processes of the microcapsules utilizing a linewidth analysis on 1H nuclear magnetic resonance (NMR) spectroscopy. Linewidth analysis on the 1H resonance signals represents that broad resonance signals of the sugar-based microcapsules are changed to relatively narrower signals as an association of cellulase enzyme. This phenomenon explains co-assembled and cross-linked microcapsule structures are destroyed or/and loosened by the enzymatic breakdowns of ester bonds in the microcapsules. Moreover, closer inspection indicates that co-assembled sorbitol molecules are released from the main networked microcapsules, additionally supporting the biodegradation properties of the microcapsules. Considering the unique features of this method, the proposed study provides valuable information about the initial biodegradation processes and mechanisms of various microcapsules.

Background: Hemorrhoids are a common anal disorder and are more frequent in women than in men. Urinary incontinence (UI) also occurs more frequently in women than in men. Although both diseases share similar risk factors, research on the association between the two diseases is lacking. This study aimed to investigate the relationship between hemorrhoids and UI in adult Korean women. Methods: This study was based on the data of the 2008-2009 Korean National Health and Nutrition Examination Survey. Logistic regression test was performed to determine the relationship between hemorrhoids and UI after adjusting for age, body mass index (BMI), smoking, heavy drinking, physical activity, education level, income, diabetes mellitus, and hypertension. Results: Analysis of the data of 8,139 adult women revealed that the prevalence of hemorrhoids, which were self-reported and diagnosed by a physician, was 17.5% and 7.9%, respectively. Both types of hemorrhoids were more prevalent in older women with spouses, those with a large waist circumference, and those with a high BMI. The prevalence of UI was significantly high in the hemorrhoid group, regardless of whether it was self-reported or diagnosed by a physician. Multiple logistic regression analyses revealed a significant association between the prevalence of UI and hemorrhoids, both of which were found to peak at 19-39 years of age. Conclusions: Our findings demonstrate that hemorrhoids are significantly correlated with UI in adult Korean women. When treating adult women with hemorrhoids, it is, therefore, necessary to consider other pelvic floor diseases such as UI.

This study introduces a temperature-responsive attractive nanoemulsion (ANE) system, which is characterized by the polymer chain conformation-driven dipolar interaction across different oil droplets in an aqueous medium. To achieve this, highly stable ANEs were produced by co-assembly of amphiphilic triblock copolymers (ATCs), poly(ethylene oxide)-b-poly(e-caprolactone)-b-poly(ethylene oxide) (PEO-b-PCL-b-PEO), with lecithin at the oil-water interface. The dipolar attraction of the methoxy terminated-PEO (mPEO) of ATCs on one drop surface with the lecithin head located on the other drop surface led to the drop-to-drop association. We showed that the efficiency of this interdrop association was dominantly influenced by the chain conformation of mPEO blocks. From dense suspension rheology studies, it was demonstrated that the ANEs formed a gel-like phase below the lower critical solution temperature (LCST) of the mPEO, but transformed to a liquid-like phase above the LCST, which occurred reversibly, thus enabling the development of temperature-responsive emulsion fluids.

The decarboxylation reaction of phenylglyoxylic acid with hydrogen peroxide is studied by real-time hyperpolarized carbon-13 nuclear magnetic resonance (13C NMR) spectroscopy at room temperature. A non-observable reaction intermediate is identified using blind selective saturation pulses in the expected chemical shift range, thereby revealing information on the reaction mechanism.

Sarcoidosis is a systemic granulomatous disease that affects a variety of organs. Although the etiology has not been fully understood, it is thought that diverse genetic and environmental factors interact with the immune system to develop granulomas. The incidence and death rate of sarcoidosis vary according to race. This study was conducted to identify the epidemiology of sarcoidosis in Korea and reveal its association with comorbid diseases such as diabetes mellitus, hypertension, and dyslipidemia in a population-based database. We retrospectively analyzed Korean National Health Insurance claims data between 2006 and 2017. The average annual incidence from 2006 to 2017 was 0.82/100 000 person-years and the all-cause death rate in sarcoidosis patients was 9.25/1000 cases. The incidence of sarcoidosis was higher in patients with diabetes mellitus, hypertension, and dyslipidemia than patients without those underlying diseases. Sarcoidosis patients with diabetes mellitus and hypertension showed an increased death rate after adjusting the confounding factors (hazard ratio [95% confidence interval], 1.66 [1.23-2.23] and 1.73 [1.29-2.31] respectively), however, patients with dyslipidemia showed a low death rate (HR = 0.64 [0.46-0.88]). In conclusion, we found that sarcoidosis is associated with diabetes mellitus, hypertension, and dyslipidemia and that diabetes mellitus and hypertension increase the risk of death in sarcoidosis patients. Extra caution is needed in sarcoidosis patients who already have these metabolic diseases.

Background: Plantar hyperhidrosis causes discomfort in daily life. However, there are few reports on sympathetic neurolysis in plantar hyperhidrosis. Case: A 19-year-old woman complained of excessive sweating of both hands and feet. Using video-assisted thoracic surgery, the patient underwent bilateral T3 sympathectomy in the department of chest surgery. One year later, she visited pain clinic with with plantar hyperhidrosis and wanted to undergo sympathetic block. Lumbar sympathetic neurolysis was performed using 2.5 ml of pure anhydrous alcohol at the L4 vertebral level. The symptoms improved after the procedure, and there were no side effects. The patient again underwent sympathetic neurolysis as the symptoms recur. Conclusions: Repeated lumbar sympathetic neurolysis was performed in a patient with plantar hyperhidrosis, and its success was confirmed during 5 years of follow-up.

Psoriasis is a chronic inflammatory skin disease associated with various factors. Recently, alterations in the gut and skin microbiomes have been shown to interact with host immunity, affect skin barrier function, as well as development and progression of psoriasis. We aimed to analyze the microbiota of the scalp of patients with psoriasis and determine the characteristics of the microbiome according to disease severity. We investigated the scalp microbiome of 39 patients with psoriasis scalp lesions and a total of 47 samples were analyzed. The patients were divided into mild, moderate, and severe groups according to the European recommendations for scalp psoriasis. For bacterial identification, we utilized the SILVA database targeting the V3 region of the 16 S rRNA gene. The mean Shannon index escalated along with disease severity, and the diversity of the scalp microbiome tended to increase with disease severity (R = 0.37, p < 0.01). The relative abundance of Pseudomonas was increased in severe scalp psoriasis (0.49 ± 0.22) compared to the mild group (0.07 ± 0.03, p = 0.029), and Diaphorobacter was enriched in the mild group (0.76 ± 0.16%) compared to the severe group (0.44 ± 0.22, p < 0.001). We identified that increased diversity of the scalp microbiome and the relative abundance of Pseudomonas are associated with the severity of scalp psoriasis.

This study investigated mental health status and quality of life in allergic disease patients compared with non-allergic controls.This study used nationwide, population-based, cross-sectional data from the Korean National Health and Nutrition Examination Survey from 2016 to 2018. The propensity matching score was used to balance age and sex distributions between the allergic disease groups and corresponding controls. Atopic dermatitis (n = 446) and asthma (n = 483) groups were compared with controls in a 1:10 ratio, and the allergic rhinitis (n = 2,357) group was compared with controls in a 1:2 ratio. Multiple logistic regression analyses were used to evaluate the odds ratios (ORs) for mental health status and health-related quality of life (HRQoL) based on the presence of allergic diseases.The ORs for severe psychological stress, psychological consultation and diagnosis of depression were more significantly increased in the asthma (OR, 1.41, 1.83, and 2.1, respectively) and allergic rhinitis groups (OR, 1.35, 1.48, and 1.83, respectively) compared with non-allergic controls after adjustment for confounding factors. The rate of severe problems in mobility was more significantly increased in the asthma group compared to controls.The results show that efforts should be made to manage psychological problems and improve HRQoL in patients with atopic dermatitis, asthma and allergic rhinitis.

Little is known about the comorbidities in actinic keratosis patients. To evaluate the association of actinic keratosis with certain malignancies. All patients with actinic keratosis (n = 61,438) and age- and sex-matched control subjects (n = 307,190) at a 5:1 ratio were enrolled using data from the Korean National Health Insurance Service between the years 2007 and 2014. In subjects with actinic keratosis, overall cancer incidence was higher than that for controls after income level, habitat, diabetes, hypertension, and dyslipidemia were adjusted (Hazard Ratio [HR] = 1.43 [95% confidence interval 1.38–1.47]). The positive association of specific cancers were observed in the following order: skin cancer (HR = 3.43 [2.47–4.75]), oral cavity and pharyngeal cancer (HR = 1.99 [1.57–2.52]), lymphoma (HR = 1.59 [1.28–1.96]), leukemia (HR = 1.35 [1.03–1.77]), prostate cancer (HR = 1.35 [1.21–1.51]), renal cancer (HR = 1.29 [1.02–1.63]), liver cancer (HR = 1.21 [1.09–1.35]), thyroid cancer (HR = 1.20 [1.05–1.38]), and gastric cancer (HR = 1.13 [1.03–1.23]). Although further research on pathologic mechanism is needed, the implications of a positive correlation between actinic keratosis and internal organ malignancies has great significance.

Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer worldwide. Recent studies have reported several genetic mutations in development of cSCC such as TP53, HRAS, and NOTCH1. Whole-exome sequencing (WES) of cSCC has not been reported in East Asian populations.We aimed to investigate genetic mutations of cSCCs in Korean patients by WES.cSCCs and paired peripheral blood samples were obtained from 19 Korean patients who underwent wide excision on the cheek from 2016 to 2020 and divided into moderate to poor-differentiated (MP-D) cSCCs (n = 9) and well-differentiated (W-D) cSCCs (n = 10) according to the histopathological evaluation. WES was performed for analysis of genomic mutations of cSCCs.The mean total mutation burden of MP-D cSCCs was higher than W-D cSCCs. Also, we observed proportionately more driver mutations in MP-D cSCC than W-D cSCC groups. CSMD3, COL22A1, FMN2, and ASXL3 mutations are highly frequent than the results of previous reports in cSCC of Caucasians.These results may aid in further our understanding of the complex process underlying tumorigenesis of cSCC in non-Caucasian populations.

Adult height is linked to the risk of several diseases, but its association with vitiligo has not been established. This study aimed to investigate the relationship between adult height and vitiligo incidence. Korean nationwide claims data from 15,980,754 individuals (20 years of age or older) who received a health checkup during the period 2005–2008, were examined. Subjects were categorized into age- and gender-specific height quintiles. Participants were followed until vitiligo diagnosis or until the end of 2015. The Cox proportional-hazards model for cumulative risk was computed for height categories. During the follow-up period, 29,196 cases (136,020,214 person-years) of newly diagnosed vitiligo were reported. A positive association was found between height and risk of vitiligo in which the hazard ratio between the highest and lowest quintiles of height was 1.36 (95% confidence interval: 1.31–1.42). While more diverse cohort studies are needed, our findings suggest that taller stature increases the risk of vitiligo.

There have been no epidemiological studies identifying associations between systemic inflammatory diseases and actinic keratosis. This study used a large nationwide database to investigate the associations between actinic keratosis and systemic inflammatory diseases. Records of patients over 20 years of age newly diagnosed with actinic keratosis (n = 64,659) from 2012 to 2017 were analysed. A control population of individuals without actinic keratosis, matched for age, sex, and year of claim, who visited an outpatient clinic, was sampled at a ratio of 1:1 (n = 64,659). Both cohorts were analysed for the presence of systemic inflammatory diseases within at least 5 years prior to diagnosis of actinic keratosis. Patients with actinic keratosis exhibited higher odds ratios for rheumatoid arthritis (1.336; 95% confidence interval (95% CI) 1.161-1.537)) and psoriasis (1.513; 95% CI 1.435-1.595) compared with the control group on multivariate analysis. However, the proportions of Behçet's disease, Crohn's disease, ulcerative colitis, and multiple sclerosis in the actinic keratosis group were not statistically significant.

This study analysed genomic mutations in basal cell carcinoma using whole exome sequencing of DNA specimens obtained from 20 Korean patients. Histological evaluation determined that 15 (75%) were low-risk basal cell carcinomas, and 5 (25%) were high-risk basal cell carcinomas. Seventy-five percent of the basal cell carcinomas harboured somatic mutations in hedge­hog pathway genes (PTCH1, 40% and SMO, 50%) and 45% harboured mutations in TP53. LRP1B was the most frequently mutated gene in high-risk basal cell carcinomas, SMO was the most frequently mutated gene in low-risk basal cell carcinomas. Specifically, LRP1B, ROS1, PTCH1, KMT2C, NSD1 and ARID1A mutations were more frequent in high-risk basal cell carcinomas than in low-risk basal cell carcinomas. However, copy number gains of the ROS1 gene were observed only in low-risk basal cell carcinomas. Other basal cell carcinoma related genes found in this study include: KDR, KMT2D, FAT1, FAT4, GRIN2A, ERBB4, NOTCH2, PDE4DIP, TET1, ZFHX3 and PREX2. These results provide insight into basal cell carcinoma in non-Caucasians.

Silicon particles in combination with the dynamic nuclear polarization (DNP) method have recently attracted attention as promising biomedical platforms for drug delivery and medical diagnostics in ...