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1.
RSC Adv ; 13(3): 1551-1557, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36688061

RESUMO

Demand for flexible transparent sensors for futuristic cars is increasing since such sensors can enhance the freedom of design and aesthetic value in the interior of cars. Herein, we propose a unique roll-to-roll UV lamination process that can expedite large-scale Ag nanowire (AgNW) transfer for a flexible capacitive sensor, using a photocurable resin composed of an epoxy acrylate oligomer, a reactive monomer (1,6-hexanediol diacrylate), and a photoinitiator (1-hydroxycyclohexyl phenyl ketone). The acryl groups in the resin were rapidly crosslinked by UV irradiation, which facilitated the AgNWs transfer from a PET to a PC substrate with the speed of 1050 cm2 min-1 and enhanced the adhesion between the AgNWs and the PC substrate. Systematic experiments were performed to determine optimal fabrication parameters with respect to the UV dose, lamination pressure, and laser dicing conditions. At the optimal fabrication conditions, the sheet resistance of AgNWs on a PC film (PC-AgNW) was as small as 36.79 Ω sq-1, which was only 3.17% deviation from that on a PET film (PET-AgNW). Furthermore, the optical transmittance of the PC-AgNW exceeded 88% over the visible range, and it was greater than that of the PET-AgNW. Notably, the sheet resistance of the PC-AgNW was almost constant after 50 taping and peeling cycles, indicating remarkable adhesion to the substrate. Furthermore, a capacitive touch sensor was fabricated using the PC-AgNW, and its switching signals were presented with and without finger touch.

2.
Micromachines (Basel) ; 13(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36422446

RESUMO

The aim of this study was to investigate properties of ceramic phosphors fabricated using nano Lu3Al5O12:Ce3+ phosphors produced with a sol-gel-combustion method. These nano Lu3Al5O12:Ce3+ phosphors had a size of about 200 nm, leading to high density when fabricated as a ceramic phosphor. We manufactured ceramic phosphors through vacuum sintering. Alumina powder was added to improve properties. We mounted the manufactured ceramic phosphor in a high-power laser beam projector and drove it to determine its optical performance. Ceramic phosphor manufactured according to our route will have a significant impact on the laser-driven lighting industry.

3.
Sci Rep ; 12(1): 20477, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443320

RESUMO

This study investigates the characteristics of a ceramic phosphor (CP) for the converter of a high-power laser diode-based automobile headlamp synthesized by high-frequency induction heated press (HFP) sintering. The CP prepared by an HFP method exhibits remarkable optical properties that are comparable to spark plasma sintering. The effects of post-treatment process for controlling residual pores, as well as sintering temperature, sintering pressure and heating rate for optimization of the HFP sintering method, were studied. The HFP sintering process can be widely used in ceramics and lighting fields because it is designed relatively low cost compared to other techniques and exhibits excellent productivity.

4.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36298320

RESUMO

Although the high incidence and recurrence rates of urothelial cancer of the bladder (UCB) are heavy burdens, a noninvasive tool for effectively detecting UCB as an alternative to voided urine cytology, which has low sensitivity, is yet to be reported. Herein, we propose an intelligent discrimination method between normal (SV-HUC-1) and cancerous (TCCSUP) urothelial cells by using a combination of micro-dimensional electrochemical impedance spectroscopy (µEIS) with machine learning (ML) for a noninvasive and high-accuracy UCB diagnostic tool. We developed a unique valved flow cytometry, equipped with a pneumatic valve to increase sensitivity without cell clogging. Since contact between a cell and electrodes is tight with a high volume fraction, the electric field can be effectively confined to the cell. This enables the proposed sensor to highly discriminate different cell types at frequencies of 10, 50, 100, 500 kHz, and 1 MHz. A total of 236 impedance spectra were applied to six ML models, and systematic comparisons of the ML models were carried out. The hyperparameters were estimated by conducting a grid search or Bayesian optimization. Among the ML models, random forest strongly discriminated between SV-HUC-1 and TCCSUP, with an accuracy of 91.7%, sensitivity of 92.9%, precision of 92.9%, specificity of 90%, and F1-score of 93.8%.


Assuntos
Espectroscopia Dielétrica , Neoplasias da Bexiga Urinária , Humanos , Teorema de Bayes , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/metabolismo , Bexiga Urinária/metabolismo , Aprendizado de Máquina
5.
J Thorac Dis ; 12(8): 4044-4056, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32944316

RESUMO

BACKGROUND: Human adenovirus (HAdV) can cause severe community-acquired pneumonia, but there are few studies on the associated cytokine patterns. The purpose of this study was to analyze the relationship between inflammatory cytokine and severity of adenovirus pneumonia. METHODS: This was a prospective observational study. We evaluated pneumonia patients admitted to the Armed Forces Capital Hospital in Korea. On admission, blood samples were acquired from patients who showed signs of pneumonia. HAdV infection was diagnosed using Real-Q RV detection Kit, and types of HAdV were confirmed by nucleotide blast analysis. We used enzyme-linked immunosorbent assays (ELISAs) to quantify the serum levels of cytokines [interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, γ-interferon (IFN-γ), and IL-10]. We evaluated clinical characteristics and cytokine patterns. RESULTS: Of 74 pneumonia patients, respiratory specimens from 43 tested positive for HAdV-55, and the other 31 tested negatives. The length of hospital stay was significantly longer in the HAdV group. The serum concentrations of IL-6, IL-8, IL-10, and IFN-γ were all significantly higher in the HAdV group. Of the 43 HAdV pneumonia patients, 6 evidenced PaO2/FiO2 (PF) ratio <300, and 37 did not. Compared to the non-hypoxemic group, the hypoxemic group showed significantly lower lymphocyte and monocyte counts, and increased IL-6 and IFN-γ concentrations. Logistic regression analysis showed that the IL-6, IL-10, and IFN-γ were significantly associated with hypoxemia in the HAdV group. The IL-6, and IFN-γ levels correlated significantly with the PF ratio. CONCLUSIONS: We found that the levels IL-6, IL-10, and IFN-γ were significantly associated with hypoxemia in patients with HAdV-55 pneumonia.

6.
Micromachines (Basel) ; 11(9)2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967186

RESUMO

We report an anti-reflective cover glass for Cu(In,Ga)Se2 (CIGS) thin film solar cells. Subwavelength structures (SWSs) were fabricated on top of a cover glass using one-step self-masked etching. The etching method resulted in dense whiskers with high aspect ratio. The produced structure exhibited excellent anti-reflective properties over a broad wavelength range, from the ultraviolet to the near infrared. Compared to a flat-surface glass, the average transmittance of the glass integrated with the SWSs improved from 92.4% to 95.2%. When the cover glass integrated with the SWSs was mounted onto the top of a CIGS device, the short-circuit current and the efficiency of the solar cell were enhanced by 4.38 and 6%, respectively, compared with a CIGS solar cell without cover glass.

7.
BMC Pulm Med ; 20(1): 22, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992279

RESUMO

BACKGROUND: We investigated the association between a combination of two markers, peripheral (PEC) and bronchoalveolar lavage (BAL) eosinophil percentage (BEP), and oxygen requirements in patients with acute eosinophilic pneumonia (AEP). METHODS: We retrospectively reviewed the medical records of patients with AEP treated at the Armed Forces Capital Hospital between May 2012 and May 2017. We used correlation analyses to assess the association between PEC/BEP and clinical outcomes in AEP patients. Receiver operating characteristic (ROC) curve analyses were used to calculate the cut-off value for BEP that categorised patients requiring a significant oxygen supply. The BAL/blood eosinophil (BBE) score was introduced to stratify patients with peripheral eosinophilia and elevated BEP. Clinical characteristics and outcomes were compared between the different groups. Multiple logistic regression was performed for significant oxygen requirements using two different models using age, C-reactive protein (CRP), smoking duration, and BBE score (model 1) and age, CRP, BEP, and PEC (model 2). RESULTS: Among the 338 patients, 99.7% were male, and their mean age was 20.4 ± 1.4 years. Only 0.6% of patients were never smokers and the mean number of smoking days was 26.2 ± 25.4. Correlation analyses revealed that both the PaO2/FiO2 ratio and duration of oxygen supply were associated with BEP. ROC curve analyses indicated a cut-off level of 41.5%. Patients with a high BBE score had favourable outcomes in terms of hypoxemia, hospital days, intensive care unit admission, oxygen supply days, and steroid treatment days. Multiple logistic regression revealed that BEP and BBE score tended to be associated with significant oxygen requirements. CONCLUSIONS: In this study, we revealed that both peripheral and BAL eosinophilia is associated with favourable outcomes in AEP patients.


Assuntos
Eosinofilia/sangue , Hipóxia/sangue , Oxigenoterapia , Eosinofilia Pulmonar/sangue , Doença Aguda , Fatores Etários , Líquido da Lavagem Broncoalveolar/citologia , Proteína C-Reativa/metabolismo , Fumar Cigarros , Feminino , Humanos , Hipóxia/metabolismo , Hipóxia/terapia , Unidades de Terapia Intensiva , Tempo de Internação , Contagem de Leucócitos , Modelos Logísticos , Masculino , Eosinofilia Pulmonar/metabolismo , Eosinofilia Pulmonar/terapia , Índice de Gravidade de Doença , Adulto Jovem
8.
Nanoscale ; 12(2): 558-562, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31777889

RESUMO

To overcome the parasitic absorption of ultraviolet (UV) light in the transparent conductive oxide (TCO) layer of flexible Cu(In,Ga)Se2 (CIGS) thin film solar cells, a CsPbBr3 perovskite nanocrystal based luminescent down-shifting (LDS) layer was integrated on CIGS solar cells fabricated on a stainless steel foil. The CsPbBr3 perovskite nanocrystal absorbs solar irradiation at wavelengths shorter than 520 nm and emits photons at a wavelength of 532 nm. These down-shifted photons pass the TCO layer without parasitic absorption and are absorbed in the CIGS absorber layer where they generate photocurrent. By minimizing the parasitic absorption in the TCO layer, the external quantum efficiency (EQE) of the CIGS solar cell with the CsPbBr3 perovskite nanocrystal layer is highly improved in the UV wavelength range between 300 and 390 nm. Additionally, in the wavelength range between 500 and 1100 nm, the EQE is improved since the surface reflectance of the CIGS device with the CsPbBr3 perovskite LDS layer was reduced. This is because the CsPbBr3 perovskite nanocrystal layer, which has an effective refractive index of 1.82 at a wavelength of 800 nm, reduces the large refractive index mismatch between air (nair = 1.00) and the TCO layer (nZnO = 1.96 at a wavelength of 800 nm). Both the short circuit current density and power conversion efficiency of the flexible CIGS solar cell integrated with the CsPbBr3 perovskite are improved by 4.5% compared with the conventional CIGS solar cell without the CsPbBr3 perovskite LDS layer.

9.
J Thorac Dis ; 11(4): 1316-1324, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31179073

RESUMO

BACKGROUND: Recent studies have suggested that low forced vital capacity (FVC) is related to respiratory symptoms with various comorbid conditions that eventually lead to physical inactivity and may be applied to subjects with airflow obstruction (AO). Therefore, this study aimed to evaluate the association between low FVC and behavior restrictions in subjects with AO. METHODS: A cross-sectional study was performed using data from the Korea National Health and Nutrition Survey conducted between 2007 and 2015. Participants aged 40 to 79 years with spirometry-defined AO (pre-bronchodilator forced expiratory volume in one second/FVC <70%) were analyzed to evaluate the association between low FVC (defined as FVC <80% predicted) and behavior restrictions. RESULTS: A total of 3,345 participants with AO were included. The proportion of subjects with low FVC varied widely according to severity of airflow limitation (0.9%, 35.5%, and 85.1% in the mild, moderate, and severe-to-very-severe AO groups, respectively). Compared to the moderate AO group with normal FVC, those with low FVC were more likely to be older, to be never- or ex-smokers, to have larger waist size with higher body mass index, and to have comorbidities such as diabetes, hypertension, dyslipidemia, and osteoporosis. Low FVC was independently associated with behavior restrictions [adjusted prevalence ratio (aPR), 1.72; 95% confidence interval (CI), 1.43-2.06] among all participants with AO, and this was most prominent in those with moderate AO (aPR, 1.65; 95% CI, 1.27-2.13). CONCLUSIONS: In subjects with moderate AO, low FVC was independently associated with behavior restrictions even after adjusting for confounding factors.

10.
Eur J Clin Microbiol Infect Dis ; 38(4): 793-800, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30693422

RESUMO

Human adenovirus (HAdV) is a common pathogen causing respiratory infections with outbreaks reported in the military and community. However, little information is available on the shedding kinetics. We performed a prospective study of immunocompetent adults confirmed with HAdV respiratory infection by multiplex real-time PCR during an outbreak of HAdV-55. Consecutive respiratory specimens of sputum or nasopharyngeal swab were collected from each patient every 2 days. Viral load was measured by real-time quantitative PCR. Of 32 enrolled patients, 27 (84.4%) had pneumonia. Five patients (15.6%) received cidofovir. Viral load was highest in the earliest samples at 8.69 log10 copies/mL. In a linear regression model, viral load declined consistently in a log-linear fashion at the rate of - 0.15 log10 copies/mL per day (95% confidence interval (CI): - 0.18, - 0.12; R2 = 0.32). However, the regression model estimated the viral shedding duration to be 55 days. The rate of decline in viral load did not differ between patients who received cidofovir and who did not. Patients with prominent respiratory symptoms or extensive involvement on chest radiograph had higher volume of viral excretion. Prolonged viral shedding was observed in otherwise healthy adults with HAdV-55 respiratory infection. This finding should be considered in the establishment of infection control and prevention strategies.


Assuntos
Infecções por Adenovirus Humanos/diagnóstico , Adenovírus Humanos/fisiologia , Infecções Respiratórias/virologia , Eliminação de Partículas Virais , Infecções por Adenovirus Humanos/tratamento farmacológico , Adenovírus Humanos/classificação , Adolescente , Surtos de Doenças , Humanos , Imunocompetência , Modelos Lineares , Masculino , Nasofaringe/virologia , Pneumonia Viral/diagnóstico , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , República da Coreia/epidemiologia , Escarro/virologia , Carga Viral , Adulto Jovem
11.
ACS Appl Mater Interfaces ; 9(30): 25404-25411, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28695727

RESUMO

Conventional Cu(In1-x,Gax)Se2 (CIGS) solar cells exhibit poor spectral response due to parasitic light absorption in the window and buffer layers at the short wavelength range between 300 and 520 nm. In this study, the CdSe/CdZnS core/shell quantum dots (QDs) acting as a luminescent down-shifting (LDS) layer were inserted between the MgF2 antireflection coating and the window layer of the CIGS solar cell to improve light harvesting in the short wavelength range. The LDS layer absorbs photons in the short wavelength range and re-emits photons in the 609 nm range, which are transmitted through the window and buffer layer and absorbed in the CIGS layer. The average external quantum efficiency in the parasitic light absorption region (300-520 nm) was enhanced by 51%. The resulting short circuit current density of 34.04 mA/cm2 and power conversion efficiency of 14.29% of the CIGS solar cell with the CdSe/CdZnS QDs were improved by 4.35 and 3.85%, respectively, compared with those of the conventional solar cells without QDs.

12.
Int J Chron Obstruct Pulmon Dis ; 11: 2757-2764, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27853363

RESUMO

PURPOSE: The association between positive bronchodilator response (BDR) at baseline and the effect of long-term bronchodilator therapy has not been well elucidated in patients with bronchiectasis. The aims of our study were to explore the association between positive BDR at baseline and lung-function improvement following long-term (3-12 months) bronchodilator therapy in bronchiectasis patients with airflow limitation. MATERIALS AND METHODS: The medical records of 166 patients with clinically stable bronchiectasis who underwent baseline pre- and postbronchodilator spirometry and repeated spirometry after 3-12 months of bronchodilator therapy were retrospectively reviewed. For analysis, patients were divided into two groups, responders and poor responders, based on achievement of at least 12% and 200 mL in forced expiratory volume in 1 second (FEV1) following bronchodilator therapy from baseline FEV1. RESULTS: A total of 57 patients (34.3%) were responders. These patients were more likely to have positive BDR at baseline than poor responders (38.6% [22 of 57] vs 18.3% [20 of 109], P=0.004). This association persisted after adjustment for other confounding factors (adjusted odds ratio 2.298, P=0.034). However, we found FEV1 improved significantly following long-term bronchodilator therapy, even in patients without positive BDR at baseline (change in FEV1 130 mL, interquartile range -10 to 250 mL; P<0.001). CONCLUSION: Positive BDR at baseline was independently associated with responsiveness to long-term bronchodilator therapy in bronchiectasis patients with airflow limitation. However, FEV1 improvement was also evident in bronchiectasis patients without positive BDR at baseline, suggesting that these patients can benefit from long-term bronchodilator therapy.


Assuntos
Obstrução das Vias Respiratórias/tratamento farmacológico , Bronquiectasia/tratamento farmacológico , Broncodilatadores/administração & dosagem , Pulmão/efeitos dos fármacos , Idoso , Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/fisiopatologia , Bronquiectasia/diagnóstico , Bronquiectasia/fisiopatologia , Broncodilatadores/efeitos adversos , Esquema de Medicação , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Espirometria , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Capacidade Vital
13.
Metab Syndr Relat Disord ; 13(3): 132-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25569241

RESUMO

BACKGROUND: Recent reports have suggested the association between emphysema and cardiovascular disease (CVD); however, there are few reports regarding association of emphysema severity with metabolic syndrome and its components representing CVD risk factors. METHODS: A retrospective cross-sectional study was performed in 2814 adult male subjects over age 40 who visited the Health Promotion Center in Samsung Medical Center for a health checkup program. RESULTS: We classified patients according to the quintiles of forced expiratory volume in 1 sec (FEV1) and emphysema index (EI). FEV1 percentage predicted values (% pred) was inversely associated with prevalence of metabolic syndrome and most of its components, such as abdominal obesity, hypertension, fasting hyperglycemia, and low high-density lipoprotein cholesterol. Although there was no association between prevalence of metabolic syndrome and EI, hypertension was positively associated with EI (P<0.001) and high triglycerides (TGs) were inversely associated with EI (P=0.021). These associations persisted after adjustment of other variables (P<0.001 in hypertension and P=0.039 in high TGs). CONCLUSION: The computed tomography-determined EI has a complex association with components of metabolic syndrome that is associated with increased prevalence of hypertension but decreased prevalence of high TGs, whereas FEV1 (% pred) has an inverse association with metabolic syndrome and most of its components with consistent direction.


Assuntos
Enfisema/complicações , Síndrome Metabólica/complicações , Tomografia Computadorizada por Raios X , Adulto , Idoso , Antropometria , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/diagnóstico por imagem , HDL-Colesterol/sangue , Estudos Transversais , Enfisema/radioterapia , Volume Expiratório Forçado , Humanos , Masculino , Síndrome Metabólica/diagnóstico por imagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Fatores de Risco
14.
Tuberc Respir Dis (Seoul) ; 77(3): 136-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25309609

RESUMO

Primary ciliary dyskinesia (PCD) is characterized by the congenital impairment of mucociliary clearance. When accompanied by situs inversus, chronic sinusitis and bronchiectasis, PCD is known as Kartagener syndrome. The main consequence of impaired ciliary function is a reduced mucus clearance from the lungs, and susceptibility to chronic respiratory infections due to opportunistic pathogens, including nontuberculous mycobacteria (NTM). There has been no report of NTM lung disease combined with Kartagener syndrome in Korea. Here, we report an adult patient with Kartagener syndrome complicated with Mycobacterium abscessus lung disease. A 37-year-old female presented to our hospital with chronic cough and sputum. She was ultimately diagnosed with M. abscessus lung disease and Kartagener syndrome. M. abscessus was repeatedly isolated from sputum specimens collected from the patient, despite prolonged antibiotic treatment. The patient's condition improved and negative sputum culture conversion was achieved after sequential bilateral pulmonary resection.

15.
J Korean Med Sci ; 29(9): 1317-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25246753

RESUMO

A 73-yr-old Korean man with permanent atrial fibrillation visited outpatient clinic with severely increased International Normalized Ratio (INR) values after taking a usual starting dosage of warfarin to prevent thromboembolism. We found out later from his blood tests that he had hyperthyroidism at the time of treatment initiation. His genetic analysis showed CYP2C9*1/*3 and VKORC1+1173TT genotypes. We suspect that both hyperthyroidism and genetic variant would have contributed to his extremely increased INR at the beginning of warfarin therapy. From this case, we learned that pharmacogenetic and thyroid function test might be useful when deciding the starting dosage of warfarin in patients with atrial fibrillation.


Assuntos
Fibrilação Atrial/diagnóstico , Citocromo P-450 CYP2C9/genética , Tireotoxicose/diagnóstico , Varfarina/sangue , Idoso , Anticoagulantes/sangue , Anticoagulantes/metabolismo , Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Cromatografia Líquida de Alta Pressão , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Espectrometria de Massas em Tandem , Tromboembolia/prevenção & controle , Vitamina K Epóxido Redutases/genética , Varfarina/metabolismo , Varfarina/uso terapêutico
16.
Tuberc Respir Dis (Seoul) ; 76(6): 292-4, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25024724

RESUMO

Primary tracheal amyloidosis (PTA) can lead to airway obstructions, and patients with severe PTA should undergo bronchoscopic interventions in order to maintain airway patency. Focal airway involvements with amyloidosis can only be treated with mechanical dilatation. However, the PTA with diffused airway involvements and concomitant cartilage destructions requires stent placement. Limited information regarding the usefulness of silicone stents in patients with PTA has been released. Therefore, we report a case of diffused PTA with tracheomalacia causing severe cartilage destruction, which is being successfully managed with bronchoscopic interventions and silicone stent placements.

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