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In an industrial context, selecting an appropriate crystal plasticity (CP) model that balances efficiency and accuracy when modelling deformation texture (DT) is crucial. This study compared DTs in IF-steel after undergoing cold rolling reductions using different CP models for two input texture scenarios. Three mean-field (MFCP) models were utilised in their most basic configurations, without considering grain fragmentation or strain hardening, in addition to a dislocation-density-based full-field (FFCP) model. The study quantitatively compared the results from the MFCP models with those from the FFCP models. Furthermore, all CP model results were compared with experimental textures obtained from electron back-scatter diffraction (EBSD) experiments. The findings revealed that certain MFCP models could predict deformation textures as accurately as the FFCP models. Notably, one of the MFCP models exhibited a superior match with experimental textures for cold rolling reductions at 60%. Upon closer examination of specific crystallographic components, it was observed that MFCP models tended to predict a stronger {111}〈211〉 component, while the full-field model favours the {111}〈011〉 component. It is crucial to emphasise the importance of quantifying the texture within individual grains when assessing the macro-level deformation texture in rolling simulations.

In this work we present a search for (solar) chameleons with the CERN Axion Solar Telescope (CAST). This novel experimental technique, in the field of dark energy research, exploits both the chameleon coupling to matter (βm) and to photons (βγ) via the Primakoff effect. By reducing the X-ray detection energy threshold used for axions from 1 keV to 400 eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600 eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of βγ≲1011 for 1

The need of an enzymatic cleaner for soft contact lens care with an improved ocular safety and stability profile led us to evaluate the use of nanoparticles (NPs) of poly(D,L-lactide-coglycolide) (PLGA) and methyl trypsin (MT). NPs were prepared by double emulsion-solvent evaporation technique. A factorial design was performed to select the lactic acid proportion in the copolymer and conditions of the second sonication. The increment in proportion of lactic acid provided higher particle size results. When the time of second sonication was decreased, the entrapment efficiency (EE) increased. PLGA 50:50 NPs were chosen for further development since PLGA 50:50H NPs settled fast with different particle size in the sediment and PLGA 75:25 NPs led to form aggregates. The addition of glycerol to the NPs provided the highest EE of MT (>90%) while the addition of Tetronic 1304 promoted the fast release of enzyme initially and decreased the zeta potential (zeta) up to neutral values after gamma irradiation. NPs are expected to be effective as a lens care cleaner after 3 days or even longer with a very low quantity of enzyme released. Formulations showed an acceptable irritation ocular tolerance after in vitro HET-CAM test and in vivo Draize test., (2009 Wiley-Liss, Inc. and the American Pharmacists Association)

Various compositions for removal of human cerumen are marketed but they are not very effective. Therefore, a proteolytic enzyme-based ceruminolytic product was developed containing the enzyme, methyl trypsin, and sodium bicarbonate. Efficacy was optimized based on in vitro testing using both human and artificial cerumen preparations. Both qualitative (visual observation) and quantitative (spectrophotometric) assessments of ceruminolytic efficacy were employed. Optimal enzyme stability was observed for the aqueous formulation at pH 4, while greater ceruminolytic efficacy was observed at pH 8. The optimal concentration range of enzyme was 150-300 absorbance U/mL based on efficacy and stability considerations. An aqueous formulation containing both methyl trypsin and sodium bicarbonate was shown to be more effective than two commercial products, Murine Ear Wax Removal Drops and Cerumenex Ear Drops. A two-part packaging system was employed to provide adequate shelf-life. Long-term stability studies confirmed that the formulation maintained >75% enzyme stability for 24 months at 5 and 25 degrees C and after reconstitution at room temperature for up to 1 day.

This study was designed to test the impact of either a strong (MTAD) or a soft (1-hydroxyethylidene-1, 1-bisphosphonate [HEPB]) chelating solution on the bond strength of Resilon/Epiphany root fillings. Both 17% EDTA and the omission of a chelator in the irrigation protocol were used as reference treatments. Forty extracted human upper lateral incisors were prepared using different irrigation protocols (n = 10): G1: NaOCl, G2: NaOCl + 17% EDTA, G3: NaOCl + BioPure MTAD (Dentsply/Tulsa, Tulsa, OK), and G4: NaOCl + 18% HEPB. The teeth were obturated and then prepared for micropush-out assessment using root slices of 1 mm thickness. Loading was performed on a universal testing machine at a speed of 0.5 mm/min. One-way analysis of variance and Tukey multiple comparisons were used to compare the results among the experimental groups. EDTA- and MTAD-treated samples revealed intermediate bond strength (0.3-3.6 MPa). The lowest bond strengths were achieved in NaOCl-treated samples (0.3-1.2 MPa, p < 0.05). The highest bond strength was reached in the HEBP-treated samples (3.1-6.1 MPa, p < 0.05). Under the present in vitro conditions, the soft chelating irrigation protocol (18% HEBP) optimized the bonding quality of Resilon/Epiphany (Resilon Research LLC, Madison, CT) root fillings.

This study was designed to compare in vitro the short-term and long-term ability to prevent through-and-through fluid movement along Resilon/Epiphany root fillings. A sample of 40 human upper incisors were prepared and assigned to experimental groups of 20 teeth each, designated as G1, Resilon/Epiphany, and G2, gutta-percha/AH Plus. Additional 10 teeth were used as controls. Each tooth was assembled in a hermetic cell to allow the evaluation of fluid filtration. After the root filling procedures, the filled roots were stored at 37 degrees C and 100% humidity for 7 days to allow setting of the sealer. Forthwith, the teeth were submitted to the first fluid flow measurement. Leakage was measured by the movement of an air bubble traveling within a pipette connected to the teeth. Shortly after the measurements, the teeth were detached from the hermetic cell and then stored in water for 14 months at 37 degrees C. At this moment, fluid filtration was re-measured. Both Kruskal-Wallis and Wilcoxon signed rank tests were applied to detect differences between the experimental groups. No differences were found between the experimental groups during the immediate measure (P > .05), whereas Resilon/Epiphany group displayed significantly more fluid movement than the gutta-percha/AH Plus group after 14 months of water storage (P < .05). The water-storage stress had no significant effect on the sealing ability of the gutta-percha/AH Plus root fillings (P > .05). The main point of our study is the fact that long-term sealing was compromised in the Resilon/Epiphany samples, when exposed to long-term water storage.

In the present study the smear layer dissolution kinetics of 18% etidronate (HEBP), 9% HEBP, and 17% ethylenediaminetetraacetic acid (EDTA) on human dentin were quantitatively and longitudinally analyzed by using a single-tooth comparative model. Coronal dentin disks were prepared from 3 maxillary human molars. A standardized smear layer was produced on the pulpal side of each disk. The smear layer-covered surface was divided into 3 similar areas. Each of these was then exposed to 1 of the 3 irrigants under investigation, whereas the others were covered with adhesive tape. Co-site image sequences of the areas under investigation were obtained after several cumulative demineralization times. Sixteen images were obtained from each dentin area of each tooth for each experimental time at 1000x magnification. An image processing and analysis sequence measured sets of images, providing data of area fraction for thousands of tubules over time and allowing us to quantitatively follow the effect of the chelating substances. The Kruskal-Wallis H test and Dunn multiple comparison test were used to analyze the data. Overall, it can be concluded that the demineralization kinetics promoted by both 9% HEBP and 18% HEBP were significantly slower than those of 17% EDTA (P < .05). In addition, the single-tooth model is advantageous over the first co-site optical microscopy dentin assessments when different chelator solutions are compared.

A precise and reproducible high-performance liquid chromatographic method for the determination of pentylenetetrazol in serum and brain tissue is described. The procedure employs reversed-phase chromatography, monitoring the eluant at 202 nm. Quantification is based on peak-height ratio of the drug to the internal standard (p-methylphenobarbital). A linear response is obtained to 100 micrograms/ml (serum) or micrograms/g (brain tissue). Within-day and between-day precision are smaller than 5%, and analytical recovery is greater than 95%. Numerous drugs tested do not interfere with the assay. The method has been used to investigate the kinetics of pentylenetetrazol distribution in serum and in discrete areas of rat brain.