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551.
Rade D. Paravina Natalie A. Pereira Sanchez Rubens N. Tango 《Color research and application》2020,45(6):1094-1100
This multicenter study evaluated the effect of harmonizing spectrophotometric (d/8°) color measurements by using actual dental materials of clinically relevant thickness and translucency as “calibration tiles.” Ten tooth-colored, 1-mm thick, resin- and ceramic-based materials were tested at the coordinating center (CC) and six research sites (RS). Correction factors were calculated for each material and each site to obtain the corrected reflection spectra from the non-corrected data set. Non-corrected (NC) and corrected (C) reflection values were converted into CIEDE2000 and CIELAB color parameters for the following comparisons: CC vs RSNC and CC vs RSC, between RSNC vs RSNC and RSC vs RSC pairs, and among RS separately (α = 0.05). Mean color differences for CC vs RSNC and corresponding CC vs RSC values were ΔE00 = 4.2 (2.6) and ΔE00 = 0.7 (0.6), respectively. Corresponding values for RSNC vs RSNC and RSC vs RSC specimen pairs were ΔE00 = 5.9 (2.9) and ΔE00 = 1.0 (0.5), respectively. The CIEDE2000 NC vs C comparison for each research site separately ranged from 0.5 to 8.5. Color differences of CC vs RSC and RSC vs RSC pairs decreased 83% to 84.5% as compared with respective color differences for non-corrected research site measurements and was RS dependent (P < .001). The obtained results validated the proposed method of harmonizing color measurements for dental application as a reliable quality control tool for dental research laboratories and industry. 相似文献
552.
Dr. Jeffery M. Tharp Dr. Natalie Krahn Prof. Dr. Umesh Varshney Prof. Dr. Dieter Söll 《Chembiochem : a European journal of chemical biology》2020,21(10):1387-1396
Genetic code expansion (GCE) has revolutionized the field of protein chemistry. Over the past several decades more than 150 different noncanonical amino acids (ncAAs) have been co-translationally installed into proteins within various host organisms. The vast majority of these ncAAs have been incorporated between the start and stop codons within an open reading frame. This requires that the ncAA be able to form a peptide bond at the α-amine, limiting the types of molecules that can be genetically encoded. In contrast, the α-amine of the initiating amino acid is not required for peptide bond formation. Therefore, including the initiator position in GCE allows for co-translational insertion of more diverse molecules that are modified, or completely lacking an α-amine. This review explores various methods which have been used to initiate protein synthesis with diverse molecules both in vitro and in vivo. 相似文献
553.
In this paper, we consider autoregressive models with conditional autoregressive variance, including the case of homoscedastic AR models and the case of ARCH models. Our aim is to test the hypothesis of normality for the innovations in a completely non‐parametric way, that is, without imposing parametric assumptions on the conditional mean and volatility functions. To this end, the Cramér–von Mises test based on the empirical distribution function of non‐parametrically estimated residuals is shown to be asymptotically distribution‐free. We demonstrate its good performance for finite sample sizes in a small simulation study. AMS 2010 Classification: Primary 62 M10, Secondary 62 G10 相似文献
554.
Kevin J Lee Griffin Wright Hannah Bryant Leigh Ann Wiggins Valeria L. Dal Zotto Michele Schuler Christopher Malozzi Michael V Cohen Natalie R Gassman 《International journal of molecular sciences》2021,22(14)
Background: Doxorubicin (Dox) is a first-line treatment for triple negative breast cancer (TNBC), but its use may be limited by its cardiotoxicity mediated by the production of reactive oxygen species. We evaluated whether vitamin D may prevent Dox-induced cardiotoxicity in a mouse TNBC model. Methods: Female Balb/c mice received rodent chow with vitamin D3 (1500 IU/kg; vehicle) or chow supplemented with additional vitamin D3 (total, 11,500 IU/kg). the mice were inoculated with TNBC tumors and treated with intraperitoneal Dox (6 or 10 mg/kg). Cardiac function was evaluated with transthoracic echocardiography. The cardiac tissue was evaluated with immunohistochemistry and immunoblot for levels of 4-hydroxynonenal, NAD(P)H quinone oxidoreductase (NQO1), C-MYC, and dynamin-related protein 1 (DRP1) phosphorylation. Results: At 15 to 18 days, the mean ejection fraction, stroke volume, and fractional shortening were similar between the mice treated with vitamin D + Dox (10 mg/kg) vs. vehicle but significantly greater in mice treated with vitamin D + Dox (10 mg/kg) vs. Dox (10 mg/kg). Dox (10 mg/kg) increased the cardiac tissue levels of 4-hydroxynonenal, NQO1, C-MYC, and DRP1 phosphorylation at serine 616, but these increases were not observed with vitamin D + Dox (10 mg/kg). A decreased tumor volume was observed with Dox (10 mg/kg) and vitamin D + Dox (10 mg/kg). Conclusions: Vitamin D supplementation decreased Dox-induced cardiotoxicity by decreasing the reactive oxygen species and mitochondrial damage, and did not decrease the anticancer efficacy of Dox against TNBC. 相似文献
555.
Abstract:This article contributes to how teams comprised mainly of knowledge workers influence project team performance. This article highlights the need to examine knowledge work and knowledge worker teams' impact on performance. Three large-sized companies were investigated through their projects, knowledge work, team environment, and team success. Results showed that the percentage of knowledge workers on a project team and project objectives had positive associations on performance. Exploratory analyses revealed that project team responsibility influenced knowledge worker project team performance as defined by projects schedule, cost, and scope. 相似文献
556.
Oksana Linnik Natalie Smirnova Oleksandr Korduban Anna Eremenko 《Materials Chemistry and Physics》2013
The gold particles of certain size were incorporated into Ti1−xZnxO2 films by sol–gel method. The synthesis conditions predetermine the size and shape of gold nanoparticles, which were monitored by the absorption spectra and SEM images. The results of Raman spectra measurements indicate that Au nanoparticles inhibit the grain growth of anatase within the film. The photocatalytic activity of Au/Ti1−xZnxO2 films in the degradation of tetracycline hydrochloride depends on the sizes of Au particles. 相似文献
557.
Dakshinamurthy Devanga Chinta Richard A. Graves Sarala Pamujula Natalie Praetorius Levon A. Bostanian 《Drug development and industrial pharmacy》2013,39(1):43-48
The objective of this study was to prepare and evaluate a novel spray-dried tableting excipient using a mixture of chitosan and lactose. Three different grades of chitosan (low-, medium-, and high-molecular-weight) were used for this study. Propranolol hydrochloride was used as a model drug. A specific amount of chitosan (1, 1.9, and 2.5 g, respectively) was dissolved in 50 mL of an aqueous solution of citric acid (1%) and later mixed with 50 mL of an aqueous solution containing lactose (20, 19.1, and 18.5 g, respectively) and propanolol (2.2 g). The resultant solution was sprayed through a laboratory spray drier at 1.4 mL/min. The granules were evaluated for bulk density, tap density, Carr index, particle size distribution, surface morphology, thermal properties, and tableting properties. Bulk density of the granules decreased from 0.16 to 0.13 g/mL when the granules were prepared using medium- or high-molecular-weight chitosan compared with the low-molecular-weight chitosan. The relative proportion of chitosan also showed a significant effect on the bulk density. The granules prepared with 1 g of low-molecular-weight chitosan showed the minimum Carr index (11.1%) indicating the best flow properties among all five formulations. All three granules prepared with 1 g chitosan, irrespective of their molecular weight, showed excellent flow properties. Floating tablets prepared by direct compression of these granules with sodium bicarbonate showed 50% drug release between 30 and 35 min. In conclusion, the spray-dried granules prepared with chitosan and lactose showed excellent flow properties and were suitable for tableting. 相似文献
558.
559.
Cartwright NA 《Journal of the Optical Society of America. A, Optics, image science, and vision》2011,28(12):2647-2654
The propagation of an electromagnetic plane-wave signal obliquely incident upon a Lorentz half-space is studied analytically. Time-domain asymptotic expressions that increase in accuracy with propagation distance are derived by application of uniform saddle point methods on the Fourier-Laplace integral representation of the transmitted field. The results are shown to be continuous in time and comparable with numerical calculations of the field. Arrival times and angles of refraction are given for prominent transient pulse features and the steady-state signal. 相似文献