727 research outputs found

    Multi-Color Luminescence Transition of Upconversion Nanocrystals via Crystal Phase Control with SiO2 for High Temperature Thermal Labels

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    Upconversion nanocrystals (UCNs)-embedded microarchitectures with luminescence color transition capability and enhanced luminescence intensity under extreme conditions are suitable for developing a robust labeling system in a high-temperature thermal industrial process. However, most UCNs based labeling systems are limited by the loss of luminescence owing to the destruction of the crystalline phase or by a predetermined luminescence color without color transition capability. Herein, an unusual crystal phase transition of UCNs to a hexagonal apatite phase in the presence of SiO2 nanoparticles is reported with the enhancements of 130-fold green luminescence and 52-fold luminance as compared to that of the SiO2-free counterpart. By rationally combining this strategy with an additive color mixing method using a mask-less flow lithography technique, single to multiple luminescence color transition, scalable labeling systems with hidden letters-, and multi-luminescence colored microparticles are demonstrated for a UCNs luminescence color change-based high temperature labeling system

    Anti-reflective nano- and micro-structures on 4H-SiC for photodiodes

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    In this study, nano-scale honeycomb-shaped structures with anti-reflection properties were successfully formed on SiC. The surface of 4H-SiC wafer after a conventional photolithography process was etched by inductively coupled plasma. We demonstrate that the reflection characteristic of the fabricated photodiodes has significantly reduced by 55% compared with the reference devices. As a result, the optical response Iillumination/Idark of the 4H-SiC photodiodes were enhanced up to 178%, which can be ascribed primarily to the improved light trapping in the proposed nano-scale texturing

    Risk stratification of symptomatic brain metastases by clinical and FDG PET parameters for selective use of prophylactic cranial irradiation in patients with extensive disease of small cell lung cancer

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    Purpose: To identify risk factors for developing symptomatic brain metastases and evaluate the impact of prophylactic cranial irradiation (PCI) on brain metastasis-free survival (BMFS) and overall survival (OS) in extensive disease small cell lung cancer (ED-SCLC). Materials and methods: Among 190 patients diagnosed with ED-SCLC who underwent FDG PET/CT and brain Magnetic Resonance Imaging (MRI) prior to treatment, 53 (27.9%) received PCI while 137 (72.1%) did not. Prognostic index predicting a high risk of symptomatic brain metastases was calculated for the group without receiving PCI (observation group, n = 137) with Cox regression model. Results: Median follow-up time was 10.6 months. Multivariate Cox regression showed that the following three factors were associated with a high risk of symptomatic brain metastases: the presence of extrathoracic metastases (p = 0.004), hypermetabolism of bone marrow or spleen on FDG PET (p < 0.001), and high neutrophil-to-lymphocyte ratio (p = 0.018). PCI significantly improved BMFS in high-risk patients (1-year rate: 94.7% vs. 62.1%, p = 0.001), but not in low-risk patients (1-year rate: 100.0% vs. 87.7%, p = 0.943). However, PCI did not improve OS in patients at high risk for symptomatic brain metastases (1-year rate: 65.2% vs. 50.0%, p = 0.123). Conclusion: Three prognostic factors (the presence of extrathoracic metastases, hypermetabolism of bone marrow or spleen on FDG PET, and high neutrophil-to-lymphocyte ratio) were associated with a high risk of symptomatic brain metastases in ED-SCLC. PCI was beneficial for patients at a high risk of symptomatic brain metastases in terms of BMFS, but not OS. Thus, selective use of PCI in ED-SCLC according to the risk stratification is recommended. (C) 2020 Elsevier B.V. All rights reserved.

    Highly efficient tandem p-i-n organic light-emitting diodes adopting a low temperature evaporated rhenium oxide interconnecting layer

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    High quality interconnection units (ICUs) with a high transparency and superior charge generating capability for tandem organic light-emitting diodes (OLEDs) are developed. The ICUs of rubidium carbonate-doped 4,7-diphenyl-1,10-phenanthroline/rhenium oxide (ReO3)-doped N,N-diphenyl-N,N-bis(1,1-biphenyl)-4,4-diamine layers with or without an additional ReO3 interlayer produce high transmittance (88%–92% at 420–700 nm) and spontaneous internal charge generation properties. A very high efficiency of ~129 cd/A has been demonstrated from only two stacked green p-i-n OLEDs by employing the developed ICUs. The relationship between the device efficiency and internal charge generation within the ICUs is further described by means of the capacitance measurements.The authors thank the MKE of Korea and Samsung SDI for their financial support of this work

    Permanent Pacemaker for Syncope after Heart Transplantation with Bicaval Technique

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    Sinus node dysfunction occurs occasionally after heart transplantation and may be caused by surgical trauma, ischemia to the sinus node, rejection, drug therapy, and increasing donor age. However, the timing and indication of permanent pacemaker insertion due to sinus node dysfunction following heart transplantation is contentious. Here, we report a case of a permanent pacemaker insertion for syncope due to sinus arrest after heart transplantation, even with a bicaval technique, which has been known to associate with few incidences of sinus node dysfunction

    Dimeric configuration of SeqA protein bound to a pair of hemi-methylated GATC sequences

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    The binding of SeqA protein to hemi-methylated GATC sequences (hemi-sites) regulates chromosome initiation and the segregation of replicated chromosome in Escherichia coli. We have used atomic force microscopy to examine the architecture of SeqA and the mode of binding of one molecule of SeqA to a pair of hemi-sites in aqueous solution. SeqA has a bipartite structure composed of a large and a small lobe. Upon binding of a SeqA molecule to a pair of hemi-sites, the larger lobe becomes visibly separated into two DNA binding domains, each of which binds to one hemi-site. The two DNA binding domains are held together by association between the two multimerization domains that make up the smaller lobe. The binding of each DNA binding domain to a hemi-site leads to bending of the bound DNA inwards toward the bound protein. In this way, SeqA adopts a dimeric configuration when bound to a pair of hemi-sites. Mutational analysis of the multimerization domain indicates that, in addition to multimerization of SeqA polypeptides, this domain contributes to the ability of SeqA to bind to a pair of hemi-sites and to its cooperative behavior

    Secondary Amyloidosis Associated with Multiple Sclerosis

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    Background Multiple sclerosis (MS) is a demyelinating disease of the central nervous system. Secondary amyloidosis can occur as a complication of chronic systemic inflammatory and infectious diseases. Until now there has been no report of secondary amyloidosis associated with MS. We report herein a case of renal biopsy-proven secondary amyloidosis in a patient with MS. Case Report A 41-year-old woman with MS was hospitalized due to aggravated quadriparesis and edema in both lower extremities. Laboratory findings showed nephrotic-range proteinuria and hypoalbuminemia. A percutaneous renal biopsy procedure was performed, the results of which revealed secondary amyloid-A-type amyloidosis associated with MS. Conclusions This is the first report of secondary amyloidosis associated with MS. J Clin Neurol 2009;5:146-14

    Impact of Depression on Work Productivity and Its Improvement after Outpatient Treatment with Antidepressants

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    AbstractObjectiveDepressive disorders influence socioeconomic burden at both the individual and organizational levels. This study estimates the lost productive time (LPT) and its resulting cost among workers with major depressive disorder (MDD) compared with a comparison group. It also estimates the change in productivity after 8 weeks of outpatient psychiatric treatment with antidepressants.MethodsWorking patients diagnosed with MDD without other major physical or mental disorders were recruited (n = 102), along with age- and sex-matched healthy controls from the Seoul Metropolitan area (n = 91). The World Health Organization's Health and Work Performance Questionnaire and the Hamilton Rating Scale for Depression were utilized to measure productivity and severity of depression, respectively, at baseline and at 8 weeks of treatment.ResultsThe LPT from absenteeism and presenteeism (reduced performance while present at work) was significantly higher among the MDD group. Workers with MDD averaged costs due to LPT at 33.4% of their average annual salary, whereas the comparison group averaged costs of 2.5% of annual salary. After 8 weeks of treatment, absenteeism and clinical symptoms of depression were significantly reduced and associated with significant improvement in self-rated job performance (31.8%) or cost savings of $7508 per employee per year.ConclusionsWe confirmed that significant productivity loss arises from MDD and that this loss can be reduced with psychiatric intervention after a time period as short as 8 weeks. Mental health professionals should work with employers to devise a cost-effective system to provide workers with accessible quality care
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