ABSTRACT
We demonstrate a spectroscopic imaging based super-resolution approach by separating the overlapping diffraction spots into several detectors during a single scanning period and taking advantage of the size-dependent emission wavelength in nanoparticles. This approach has been tested using off-the-shelf quantum dots (Invitrogen Qdot) and in-house novel ultra-small (~3 nm) Ge QDs. Furthermore, we developed a method-specific Gaussian fitting and maximum likelihood estimation based on a Matlab algorithm for fast QD localisation. This methodology results in a three-fold improvement in the number of localised QDs compared to non-spectroscopic images. With the addition of advanced ultra-small Ge probes, the number can be improved even further, giving at least 1.5 times improvement when compared to Qdots. Using a standard scanning confocal microscope we achieved a data acquisition rate of 200 ms per image frame. This is an improvement on single molecule localisation super-resolution microscopy where repeated image capture limits the imaging speed, and the size of fluorescence probes limits the possible theoretical localisation resolution. We show that our spectral deconvolution approach has a potential to deliver data acquisition rates on the ms scale thus providing super-resolution in live systems.
Subject(s)
Fluorescence , Quantum Dots , Spectrometry, Fluorescence , Likelihood FunctionsABSTRACT
BACKGROUND: Sarcoidosis is associated with a poor prognosis. There is a lack of data examining the outcomes and readmission rates of sarcoidosis patients with heart failure (SwHF) and without heart failure (SwoHF). We aimed to compare the impact of non-ischemic heart failure on outcomes and readmissions in these two groups. METHODS: The US Nationwide Readmission Database was queried from 2010 to 2019 for SwHF and SwoHF patients identified using the International Classification of Diseases, 9th and 10th Editions. Those with ischemic heart disease were excluded, and both cohorts were propensity matched for age, gender, and Charlson Comorbidity Index (CCI). Clinical characteristics, length of stay, adjusted healthcare-associated costs, 90-day readmission and mortality were analyzed. RESULTS: We identified 97,961 hospitalized patients (median age 63 years, 37.9% male) with a diagnosis of sarcoidosis (35.9% SwHF vs 64.1% SwoHF). On index admission, heart failure patients had higher prevalences of atrioventricular block (3.3% vs 1.4%, P < .0001), ventricular tachycardia (6.5% vs 1.3%, P < .0001), ventricular fibrillation (0.4% vs 0.1%, P < .0001) and atrial fibrillation (22.1% vs 7.5%, P < .0001). SwHF patients were more likely to be readmitted (hazard ratio 1.28, P < .0001), had higher length of hospital stay (5 vs 4 days, P < .0001), adjusted healthcare-associated costs ($9,667.0 vs $9,087.1, P < .0001) and mortality rates on readmission (5.1% vs 3.8%, P < .0001). Predictors of mortality included heart failure, increasing age, male sex, higher CCI, and liver disease. CONCLUSION: SwHF is associated with higher rates of arrhythmia at index admission, as well as greater hospital cost, readmission and mortality rates compared to those without heart failure.
ABSTRACT
PURPOSE: This study compared the surface hardness, flexural strength, and flexural modulus of a light- and heat-cured urethane dimethacrylate (UDMA) to two conventional polymethyl methacrylate (PMMA) denture base resins. The effect of less-than-optimal processing condition on the hardness of internal and external surfaces of UDMA specimens was also investigated. MATERIALS AND METHODS: The materials tested were Eclipse (light- and heat-cured UDMA), Meliodent (heat-cured PMMA), and Probase Cold (auto-cured PMMA). Eclipse specimens were prepared by adapting the material onto the master cast and light curing in the processing unit for 10 minutes. Meliodent and Probase Cold specimens were prepared according to the manufacturers' instructions. Twenty rectangular specimens measuring 65 x 10 x 2.5 mm(3) were prepared for each material. They were stored in water at 37 degrees C for 30 days before testing. The surface hardness was measured using Vickers Hardness (VHN) test, and flexural strength and flexural modulus were measured using a 3-point bending test. Twenty-five additional Eclipse specimens were similarly prepared and were processed at various times of less than 20 minutes of curing. Vickers Hardness was determined on both the external and internal surfaces of specimens. Data were analyzed using a one-way ANOVA for comparisons of hardness, flexural strength, and flexural modulus between the three denture base materials and for hardness values of both the internal and external surface of Eclipse specimens with curing times. Post hoc analyses (Scheffé test) determined the difference between the groups. Student t-test was used for comparison of hardness between the external and internal surfaces of Eclipse specimens. RESULTS: The hardness (VHN) values were 19.4 +/- 0.7, 17.0 +/- 0.4, and 16.0 +/- 0.4; the flexural strengths (MPa) were 103 +/- 4, 78 +/- 3, and 63 +/- 4; and the flexural moduli (MPa) were 2498 +/- 143, 1969 +/- 55, and 1832 +/- 89 for Eclipse, Meliodent, and Probase Cold materials, respectively. A comparison among the three polymers showed there were significant differences in surface hardness, flexural strength, and flexural modulus (p < 0.05). No significant difference in surface hardness (VHN) between the internal (19.1 +/- 0.6 to 19.4 +/- 0.7) and external surfaces (18.9 +/- 0.4 to 19.2 +/- 0.6) of irradiated Eclipse specimens was observed at 10-, 12-, and 14-minute polymerization times. CONCLUSION: The surface hardness, flexural strength, and flexural modulus of light- and heat-cured UDMA (Eclipse) were significantly higher than the values obtained for heat-only cured (Meliodent) and auto-cured (Probase Cold) PMMA denture base systems.