Decay Process for Three - Species Reaction - Diffusion System

We propose the deterministic rate equation of three-species in the reaction - diffusion system. For this case, our purpose is to carry out the decay process in our three-species reaction-diffusion model of the form $A+B+C\to D$. The particle density and the global reaction rate are also shown analytically and numerically on a two-dimensional square lattice with the periodic boundary conditions. Especially, the crossover of the global reaction rate is discussed in both early-time and long-time regimes.Comment: 6 pages, 3 figures, Late

Real world outcomes using 20 mm balloon expandable SAPIEN 3/ultra valves compared to larger valves (23, 26, and 29 mm)-a propensity matched analysis

OBJECTIVE/BACKGROUND: Small balloon expandable valves have higher echocardiographic transvalvular gradients and rates of prosthesis-patient mismatch (PPM) compared to larger valves. However, the impact of these echocardiographic findings on clinical outcomes is unknown. We sought to determine the clinical outcomes of 20 mm SAPIEN 3 (S3 BEV) compared to larger S3 BEV in relation to echocardiographic hemodynamics. METHODS: Using the STS/ACC transcatheter valve registry, we performed a propensity-matched comparison of patients undergoing treatment of native aortic valve stenosis using transfemoral, balloon-expandable implantation of 20 mm and ≥ 23 mm S3 BEVs. Baseline and procedure characteristics, echocardiographic variables and survival were analyzed. Multivariable logistic regression was used to identify predictors of 1-year mortality. RESULTS: After propensity matching of the 20 mm and ≥ 23 mm SAPIEN 3 valves, 3,931 pairs with comparable baseline characteristics were identified. Small valves were associated with significantly higher echocardiographic gradients at discharge (15.7 ± 7.1 mmHg vs. 11.7 ± 5.5 mmHg, p \u3c 0.0001) and severe PPM rates (21.5% vs. 9.7%, p \u3c 0.0001). There was no significant difference in 1-year all-cause mortality (20 mm: 13.0% vs. ≥23 mm: 12.7%, p = 0.72) or other major adverse event rates and outcomes between the two cohorts. Based on a multivariable analysis, elevated discharge mean gradient (\u3e20 mmHg), severe PPM and the use of 20 mm versus ≥23 mm were not independent predictors of 1-year mortality. CONCLUSION: SAPIEN 3 20 mm valves were associated with higher echocardiographic gradients, and severe PPM rates compared to larger valves but these factors were not associated with significant differences in 1-year all-cause mortality or rehospitalization

An independent assessment of uncertainty for radiocarbon analysis with the new generation high-yield accelerator mass spectrometers

ABSTRACT. The radiocarbon dating facility at the Centre for Isotope Research, University of Groningen went through a major upgrade in 2017 and this included installation of a MICADAS accelerator mass spectrometer (AMS). In the first 18 months, we performed 4000 sample and 3000 reference measurements. A careful evaluation of those measurement results is presented, to characterize the various sources of uncertainty and to ultimately assign, for every sample measurement, a realistic expanded uncertainty. This analysis was performed on the measurements of secondary references and sample duplicates in various phases of their processing steps. The final expanded uncertainty includes both the 14C measurement uncertainties and uncertainties originating from pretreatment steps. Where the 14C measurement uncertainty includes straightforward uncertainties arising from Poisson statistics, background subtraction, calibration on Oxalic Acid II and δ13C correction, the uncertainties originating from pretreatment steps are based on the spread of actual measurement results for secondary references and sample duplicates. We show that the 14C measurement uncertainty requires expansion, depending on the number of processing steps involved prior to a 14C measurement, by a maximum factor of 1.6 at our laboratory. By using these expansion (multiplication) factors, we make our reported uncertainty both more realistic and reliable

Formation of Liesegang patterns: A spinodal decomposition scenario

Spinodal decomposition in the presence of a moving particle source is proposed as a mechanism for the formation of Liesegang bands. This mechanism yields a sequence of band positions x_n that obeys the spacing law x_n~Q(1+p)^n. The dependence of the parameters p and Q on the initial concentration of the reagents is determined and we find that the functional form of p is in agreement with the experimentally observed Matalon-Packter law.Comment: RevTex, 4 pages, 4 eps figure

The new paradigm of hepatitis C therapy: integration of oral therapies into best practices.

Emerging data indicate that all-oral antiviral treatments for chronic hepatitis C virus (HCV) will become a reality in the near future. In replacing interferon-based therapies, all-oral regimens are expected to be more tolerable, more effective, shorter in duration and simpler to administer. Coinciding with new treatment options are novel methodologies for disease screening and staging, which create the possibility of more timely care and treatment. Assessments of histologic damage typically are performed using liver biopsy, yet noninvasive assessments of histologic damage have become the norm in some European countries and are becoming more widespread in the United States. Also in place are new Centers for Disease Control and Prevention (CDC) initiatives to simplify testing, improve provider and patient awareness and expand recommendations for HCV screening beyond risk-based strategies. Issued in 2012, the CDC recommendations aim to increase HCV testing among those with the greatest HCV burden in the United States by recommending one-time testing for all persons born during 1945-1965. In 2013, the United States Preventive Services Task Force adopted similar recommendations for risk-based and birth-cohort-based testing. Taken together, the developments in screening, diagnosis and treatment will likely increase demand for therapy and stimulate a shift in delivery of care related to chronic HCV, with increased involvement of primary care and infectious disease specialists. Yet even in this new era of therapy, barriers to curing patients of HCV will exist. Overcoming such barriers will require novel, integrative strategies and investment of resources at local, regional and national levels

Liesegang patterns: Effect of dissociation of the invading electrolyte

The effect of dissociation of the invading electrolyte on the formation of Liesegang bands is investigated. We find, using organic compounds with known dissociation constants, that the spacing coefficient, 1+p, that characterizes the position of the n-th band as x_n ~ (1+p)^n, decreases with increasing dissociation constant, K_d. Theoretical arguments are developed to explain these experimental findings and to calculate explicitly the K_d dependence of 1+p.Comment: RevTex, 8 pages, 3 eps figure

Diffusion-Limited Annihilation with Initially Separated Reactants

A diffusion-limited annihilation process, A+B->0, with species initially separated in space is investigated. A heuristic argument suggests the form of the reaction rate in dimensions less or equal to the upper critical dimension $d_c=2$. Using this reaction rate we find that the width of the reaction front grows as $t^{1/4}$ in one dimension and as $t^{1/6}(\ln t)^{1/3}$ in two dimensions.Comment: 9 pages, Plain Te

TCT-378 Not Every TEE Is a “Standard of Care” TEE

Background: Intraprocedural structural heart imaging is more challenging and has unique differences from standard of care (SOC) imaging. However, the variations in time and complexity of different types of SOC transesophageal echocardiographs (TEEs) versus interventional TEEs is not well studied. In this study, we aim to compare the complexity of SOC nonvalvular indication TEE with SOC valvular TEE studies and interventional TEEs performed in the guidance of transcatheter edge-to-edge repair (TEER) MitraClip (Abbott Vascular) procedures. Methods: A retrospective case-control analysis was performed on 200 patients who underwent TEE in the Henry Ford Health System. One hundred cases of interventional TEE-guided TEER were compared with 73 nonvalvular (endocarditis and stroke evaluation) SOC TEEs and 27 valvular (preprocedural mitral, aortic, and tricuspid valve evaluations) SOC TEEs. Complexity was quantified by the total procedure duration, the total number of images, and the number of 3-dimensional (3D) clips captured. The mean, median, and SD were compared between these groups. The Kruskal-Wallis test was used to evaluate statistical significance. Results: The mean duration of TEE procedures, the number of images, and the number of 3D clips were all significantly higher in the interventional imaging TEER group compared with the noninterventional groups (P \u3c 0.0001) (Table 1). The duration and number of images were also significantly higher among valvular compared with nonvalvular SOC TEE groups (P \u3c 0.0002) as well as number of 3D clips (P \u3c 0.0012). Conclusion: Interventional TEE was more complicated and time-consuming compared with SOC TEE performed for both nonvalvular and valvular indications. The latter was also more complex than SOC nonvalvular TEE. This is the first study of its kind demonstrating objective differences between interventional and 2 SOC TEE groups. These results emphasize the need of dedicated training for intraprocedural imaging as well as restructuring of reimbursement codes. Categories: STRUCTURAL: Valvular Disease: Mitra

TCT-374 Structural Heart Intraprocedural Versus Nonprocedural Transesophageal Echocardiography: A Quantitative Analysis of Complexity

Background: Transesophageal echocardiography (TEE) is an essential tool in many structural heart procedures, such as transcatheter mitral valve edge-to-edge repair (TEER). Interventional procedural TEE requires a unique skill set. This study aims to evaluate the complexity of interventional structural heart TEE used to guide TEER compared with standard of care (SOC) TEE studies performed at a single center. Methods: A retrospective case-control analysis was performed of 200 patients who underwent TEE in the Henry Ford Health System. One hundred cases of interventional TEE-guided TEER were compared with 100 controls of SOC TEE. Complexity was quantified by the total duration of the procedure, the total number of images, and the number of 3-dimensional clips captured. The mean, median, and SD were compared between these 2 groups. Wilcoxon rank sum tests were used to evaluate statistical significance. Results: One hundred intraprocedural TEE studies to guide TEER and 100 SOC TEE studies were analyzed. The mean duration of TEE procedures, the number of images, and the number of 3-dimensional clips were all significantly higher in the TEER group (P \u3c 0.0001) (Table 1). Conclusion: Interventional TEE guidance for TEER is significantly more complex and more time-consuming than SOC TEE. This is the first large-scale study demonstrating objective differences between interventional and SOC TEE. This conclusion implicates the necessity of dedicated training programs for interventional imaging, in addition to the necessity of reviewing the current reimbursement codes to account for such a difference. Categories: STRUCTURAL: Valvular Disease: Mitra

Preferences and skills of Indian public sector teachers

With a sample of 700 future public sector primary teachers in India, a Discrete Choice Experiment is used to measure job preferences, particularly regarding location. General skills are also tested. Urban origin teachers and women are more averse to remote locations than rural origin teachers and men respectively. Women would require a 26-73 percent increase in salary for moving to a remote location. The results suggest that existing caste and gender quotas can be detrimental for hiring skilled teachers willing to work in remote locations. The most preferred location is home, which supports decentralised hiring, although this could compromise skills