Search results for "grain"
showing 10 items of 752 documents
Shakedown analysis for a class of strengthening materials within the framework of gradient plasticity
2010
Abstract The classical shakedown theory is extended to a class of perfectly plastic materials with strengthening effects (Hall–Petch effects). To this aim, a strain gradient plasticity model previously advanced by Polizzotto (2010) is used, whereby a featuring strengthening law provides the strengthening stress, i.e. the increase of the yield strength produced by plastic deformation, as a degree-zero homogeneous second-order differential form in the accumulated plastic strain with associated higher order boundary conditions. The extended static (Melan) and kinematic (Koiter) shakedown theorems are proved together with the related lower bound and upper bound theorems. The shakedown limit loa…
Crossover, double-blind clinical trial comparing almotriptan and ergotamine plus caffeine for acute migraine therapy
2007
In this randomized, double-blind, crossover clinical trial, adult patients treated two migraine attacks: one with almotriptan 12.5 mg and the other with ergotamine 2 mg plus caffeine 200 mg. Treatment with almotriptan was associated with a significantly greater proportion of patients achieving 2-h pain free (20.9% vs. 13.7%; P < 0.05) and 2-h pain relief (57.7% vs. 44.5%; P < 0.01) compared with ergotamine plus caffeine therapy; significant differences were not seen at 1 h. Rates for sustained pain free and sustained pain free plus no adverse events (AEs) also were significantly greater after almotriptan treatment than after the use of ergotamine plus caffeine (P < 0.05). Almotriptan was as…
Influence of M23C6 carbides on the heterogeneous strain development in annealed 420 stainless steel
2020
Understanding the local strain enhancement and lattice distortion resulting from different microstructure features in metal alloys is crucial in many engineering processes. The development of heterogeneous strain not only plays an important role in the work hardening of the material but also in other processes such as recrystallization and damage inheritance and fracture. Isolating the contribution of precipitates to the development of heterogeneous strain can be challenging due to the presence of grain boundaries or other microstructure features that might cause ambiguous interpretation. In this work a statistical analysis of local strains measured by electron back scatter diffraction and …
Identification and quantitation of tocopherols, carotenoids and triglycerides in edible Pistacia lentiscus oil from Tunisia
2020
International audience; The fruits of Pistacia lentiscus are a source of a fixed oil used in some forested areas for culinary purposes and in traditional medicines. The aim of this study was to evaluate the levels of tocopherols, carotenoids and triglycerides in this oil using high-performance liquid chromatography (HPLC). The results demonstrated the presence of two vitamin E isomers; α- and γ-tocopherols, at respective concentrations of 119 mg and 23 mg per kg of oil. β-carotene, lutein and zeaxanthin were the principal carotenoid molecules identified. β-carotene was the main molecule present, with a level of 6.13 mg/kg oil. Di-unsaturated triglycerides comprised more than half of the tot…
X-ray Computed Tomography for Capillary Collapse of Loose Unsaturated Sand
2016
Abstract The collapse of unsaturated soils consists of the reduction in volume upon wetting at constant total stress. Several studies at the macro scale outline the influence of initial void ratio, confining pressure and matric suction on the onset of collapse of standard laboratory specimens. Conversely, few observations at the micro scale are available in the literature, although the influence of the particles arrangement and intergranular bonding has been formerly supposed. The collapse of fine sand derived by a pyroclastic soil of Southern Italy is investigated in this paper at the microscale using the X-ray Computed Tomography. The experimental procedure, formerly tested on similar pyr…
Influence of HCl pretreatment and organo-mineral complexes on laser diffraction measurement of loess–paleosol-sequences
2016
Abstract The influence of different sample pretreatment methods on grain size distributions in particle size analysis has been subject to controversial discussions. Standard sample preparation typically comprises the disaggregation of aggregated and agglomerated particles into single primary particles, i.e., the organic binding material is oxidized by hydrogen peroxide (H2O2) and the contained carbonates are dissolved by hydrochloric acid (HCl). The aim of this study is to evaluate the effects of HCl treatment on grain size analyses of Late Pleistocene and Holocene loess–paleosol-sequences investigated by a Beckman Coulter LS 13320 laser particle analyzer. For this purpose, samples from two…
Fluorine-containing drugs approved by the FDA in 2019
2020
Abstract Eleven new fluorine-containing FDA-approved drugs have been profiled and details of their discovery and preparation are discussed. Therapeutic areas include schizophrenia, migraine, multiple sclerosis, insomnia, rheumatoid arthritis, anti-tuberculosis, breast cancer, lymphoma kinase inhibitor, serotonin receptor antagonist. New pharmaceuticals feature four examples of aromatic fluorine, three aromatic CF3 group, three aliphatic CF3 and one compound with aromatic CF3O group. Furthermore, among the new compounds, six are chiral and seven are derived from tailor-made amino acids.
Properties of sea urchin coelomocyte agglutinins
1996
We examined some biological activities of a 200-kDa glycoprotein, referred to as Paracentrotus lividus vitellogenin, contained both in the coelomic fluid and in a subpopulation of coelomocytes called «colourless spherula cells». Cell-free coelomic fluid, coelomocyte lysate and supernatant obtained after coelomocyte washings were assayed for hemagglutinating activity. All samples agglutinated rabbit erythrocytes in a calcium-dependent way. The comparison between the electrophoretic patterns of erythrocyte lysates, before and after incubation with the coelomic fluid, revealed that a 200-kDa band was obtained from membranes of agglutinated erythrocytes. In addition, polyclonal antibodies again…
Fast Solution Precursor Synthesis of the 2223 Phase: the Role of Lead in the Reaction Pathway
1994
ABSTRACTValuable mechanistic information, about the reaction pathway in the formation of the 2223 phase, has been obtained by the use of a solution synthesis route. The presence of lead in the starting mixture has remarkable effects on the nature and stability of the different intermediates: i) the grain size and morphology of Bi2CuO4 is severely changed, ii) calcium carbonate is partially decomposed to yield the calcium plumbate, iii) the 2201 phase results stabilized against the formation of the collapsed phase Bi17Sr16Cu7O49-δ, iv) the melting point of the intermediate 2212 is lowered by about 10 °C. All these effects, due to lead substitution, contribute to promote the formation of the …
Can eadache impair intellectual abilities in children? An observational study
2012
Background: The purpose of this study was to assess the cognitive functioning of children affected by headache, pinpointing the differences in intelligence style between subjects affected by migraine without aura and subjects with tension-type headache. Methods: The study population consisted of 147 children (mean age 10.82 ± 2.17 years) with headache, recruited from the Headache Center for Developmental Age, Child and Adolescent Neuropsychiatry Clinic, Second University of Naples. Cognitive profiling was performed using Weschler Intelligence Scale for Children Third Edition throughout the sample. According to the International Classification of Headache Disorders II criteria for pediatric …