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Jurassic age volcanic rocks of the Stonyford volcanic complex (SFVC) comprise three distinct petrological groups based on their whole-rock geochemistry: (1) oceanic tholeiites; (2) transitional alkali basalts and glasses; (3) high-Al, low-Ti tholeiites. Major and trace element, and Sr–Nd–Pb isotopic data indicate that the oceanic tholeiites formed as low-degree partial melts of normal mid-ocean ridge basalt (N-MORB)-source asthenosphere similar in isotope composition to the East Pacific Rise today; the alkalic lavas were derived from an enriched source similar to that of E-MORB. The high-Al, low-Ti lavas resemble second-stage melts of a depleted MORB-source asthenosphere that formed by melting spinel lherzolite at low pressures. Trace element systematics of the high-Al, low-Ti basalts show the influence of an enriched component, which overprints generally depleted trace element characteristics. Tectonic discrimination diagrams show that the oceanic tholeiite and alkali suites are similar to present-day basalts generated at mid-oceanic ridges. The high-Al, low-Ti suite resembles primitive arc basalts with an enriched, alkali basalt-like overprint. Isotopic data show the influence of recycled components in all three suites. The SFVC was constructed on a substrate of normal Coast Range ophiolite in an extensional forearc setting. The close juxtaposition of the MORB-like olivine tholeiites with alkali and high-Al, low-Ti basalts suggests derivation from a hybrid mantle source region that included MORB-source asthenosphere, enriched oceanic asthenosphere, and the depleted supra-subduction zone mantle wedge. We propose that the SFVC formed in response to collision of a mid-ocean ridge spreading center with the Coast Range ophiolite subduction zone. Formation of a slab window beneath the forearc during collision allowed the influx of ridge-derived magmas or the mantle source of these magmas. Continued melting of the previously depleted mantle wedge above the now defunct subduction zone produced strongly depleted high-Al, low-Ti basalts that were partially fertilized with enriched, alkali basalt-type melts and slab-derived fluids. [ABSTRACT FROM AUTHOR]

The Coast Range ophiolite (CRO) in northern California includes two distinct remnants. The Elder Creek ophiolite is a classic suprasubduction zone ophiolite with three sequential plutonic suites (layered gabbro, wehrlite-pyroxenite, quartz diorite), a mafic to felsic dike complex, and mafic-felsic volcanic rocks; the entire suite is cut by late mid-oceanic-ridge basalt (MORB) dikes and overlain by ophiolitic breccia. The Stonyford volcanic complex (SFVC) comprises three volcanic series with intercalated chert horizons that form a submarine volcano enclosed in sheared serpentinite. Structurally below this seamount are mélange blocks of CRO similar to Elder Creek. U/Pb zircon ages from plagiogranite and quartz diorites at Elder Creek range in age from 165 Ma to 172 Ma. U/Pb zircon ages obtained from CRt mé1ange blocks below the SFVC are similar (166-172 Ma). 40Ar-39Ar ages of alkali basalt glass in the upper SFVC are all younger at ≈164 Ma. Radiolarians extracted from chert lenses intercalated with basalt in the SFVC indicate that the sedimentary strata range in age from Bathonian (Unitary Association Zone 6-6 of Baumgartner et al., 1995a) near the base of the complex to late Callovian to early Kimmeridgian (Unitary Association Zones 8-10) in the upper part. The SFVC sedimentary record preserves evidence of a major faunal change wherein relatively small sized, polytaxic radiolarian faunas were replaced by very robust, oligotaxic, nassellarian-dominated faunas that included Praeparvicingula spp. We suggest that CRt formation began after the early Middle Jurassic (172-180 Ma) collision of an exotic or fringing arc with North America and initiation of a new or reconfigured east-dipping subduction zone. The data show that the CRt formed prior to the Late Jurassic Nevadan orogeny, probably by rapid forearc extension above a nascent subduction zone. We infer that CRt spreading ended with the collision of an oceanic spreading center ca. 164 Ma, coincident with the oldest high-grade blocks in the structurally underlying Franciscan assemblage. We further suggest that the "classic" Nevadan orogeny represents a response to spreading center collision, with shallow subduction of young lithosphere causing the initial compressional deformation and with a subsequent change in North American plate motion to rapid northward drift (J2 cusp) causing sinistral transpression and transtension in the Sierra foothills. These data are not consistent with models for Late Jurassic arc collision in the Sierra foothills or a backarc origin for the CRO. [ABSTRACT FROM AUTHOR]

Abstract: The equilibrium unfolding transitions of Cro repressor variants, dimeric variant Cro F58W and monomer Cro K56[DGEVK]F58W, have been studied by urea and guanidine hydrochloride to probe the folding mechanism. The unfolding transitions of a dimeric variant are well described by a two state process involving native dimer and unfolded monomer with a free energy of unfolding, , of ∼10–11kcal/mol. The midpoint of transition curves is dependent on total protein concentration and is independent of protein concentration, as expected for this model. Unfolding of Cro monomer is well described by the standard two state model. The stability of both forms of protein increases in the presence of salt but decreases with the decrease in pH. Because of the suggested importance of a N2⇔2F dimerization process in DNA binding, we have also studied the effect of sodium perchlorate, containing the chaotropic perchlorate anion, on the conformational transition of Cro dimer by CD, fluorescence and NMR (in addition to urea and guanidine hydrochloride) in an attempt both to characterize the thermodynamics of the process and to identify conditions that lead to an increase in the population of the folded monomers. Data suggest that sodium perchlorate stabilizes the protein at low concentration (<1.5M) and destabilizes the protein at higher perchlorate concentration with the formation of a “significantly folded” monomer. The tryptophan residue in the “significantly folded” monomer induced by perchlorate is more exposed to the solvent than in native dimer. [Copyright &y& Elsevier]

The multi-site study (MSS) concept is not new and was already being used by the Swiss plant protection and pharmaceutical industries, across all areas of expertise, 11 years before the publication of the Organisation for Economic Co-operation and Development (OECD) Consensus Document No. 13. The need for this type of study set-up was and remains unavoidable, not only because of the way in which field studies for the determination of product residues in food are conducted in the plant protection industry, but also because of the fractionation of other study types ( e.g. toxicology studies) and the related subcontracting to contract labs as a consequence of insufficient capacity and/or lack of expertise as well as for cost reduction reasons. This paper deals with the historical background of the introduction of the MSS concept, its development, known facts, reasons for its extension to other areas, frequent difficulties in its daily implementation, regulatory and monitoring weaknesses, as well as, consequences and measures. Statements are corroborated by practical examples. Experience shows that there are weaknesses ( differences) among the various national Compliance Monitoring Authorities in charge of inspecting MMSs and there are still substantial differences from country to country regarding the interpretation and enforcement of GLP principles. Doubts are arising about the sense of OECD Mutual Joint Visits, and the mutual acceptance of data appears to be at jeopardy. A lot of time and patience is still needed to improve harmonisation at the international level so that GLP principles are followed uniformly across companies and countries. There is also the need for increased involvement of quality assurance units and Compliance Monitoring Authorities. [ABSTRACT FROM AUTHOR]

The phase-formation process in the disperse β-SiC + SiO + CrO + C system treated in vacuum at 1273, 1473, 1673, and 1873 K was studied by X-ray phase analysis, IR spectroscopy, EPR, and other methods. It was found that at treatment temperatures of 1273, 1473, and 1673 K, the major process is carbothermal reduction of CrO and SiO with the formation of chromium carbosilicide and chromium carbide (CrC). At T = 1873 K, on the surface of the SiC particles, metastable chromium silicate forms on the base of SiO and CrO. The reduction of CrSiO by silicon carbide is accompanied by the formation of CrSi, CrSi, and chromium carbosilicide. The phase composition of the products of interaction and their distribution over the volume of the composite powder and ceramic material are determined by the dispersion composition of the starting SiC powder and by the degree of development of reduction processes in local volumes of the disperse and compacted material. [ABSTRACT FROM AUTHOR]

Clinical trials with pharmaceuticals or medical devices make complex demands on sponsors and participating centers. During the past two decades, sponsors have increasingly delegated regulatory and organizational tasks to clinical research organizations (CRO). As a rule, these companies are the main interface for the collaboration with the participating study centers. The main purpose of the participation is the support of the study centers for achieving an optimal study quality. The study centers involved in the DOG working group on clinical study centers perceived varying experiences in the collaboration with CROs. In the future these experiences will be systematically assessed at the participating study centers and analyzed by the coordinating investigator. Reflecting these experiences to the respective CROs and the delegating sponsors will contribute to the quality of support by CROs and herewith to the quality of clinical trials. This paper presents which areas of collaboration will be assessed and analyzed., (© 2021. The Author(s).)

• A multi-objective hybrid method for task scheduling problem is proposed. • Represented the NP-Complete task scheduling problem in the form of mathematical model. • Proposed a task scheduling framework for processing the applications/tasks in efficient way. • The proposed method is a hybrid optimization technique using the Chemical Reaction Optimization (CRO) and Particle Swarm Optimization (PSO). • Proposed CR-PSO framework is simulated at CloudSim simulator to evaluated the performance. In cloud computing, efficient task scheduling espouses many challenges. To schedule the multiple cloudlets with deadline constraints on hybrid cloud resources while meeting the various quality requirements is a challenging issue. The purpose of this research work is to address the task scheduling problem of cloud computing. A novel hybrid task scheduling algorithm named Chemical Reaction Partial Swarm Optimization has been proposed for the allotment of multiple independent tasks on the available virtual machines. It enhances the classical chemical reaction optimization and partial swarm optimization and does hybridization by combining the features for the optimal schedule sequence where tasks can be processed based upon the demand and deadline simultaneously to improve the quality in terms of factors like cost, energy, and makespan. We present the comprehensive simulation experiment using the CloudSim toolkit, which shows the effectiveness of the proposed algorithms. To analyse average execution time, comparative experiments have been carried out using various combinations of virtual machines and the number of tasks. The results bring out a significant reduction in execution time of the order of 1–6 percent, which further improves even more than 10 percent in some cases. The results of the makespan reflect the effectiveness of the algorithm in order of 5–12 percent, and the outcome of total cost 2–10 percent and energy consumption rate shows the 1–9 percent improvement. [ABSTRACT FROM AUTHOR]

The oxidation behavior at 900°C of pure Cr and Cr implanted with 2×10 Y ions/cm was studied. The kinetics of oxidation were measured thermogravimetrically and manometrically. The mechanisms of oxide growth were studied usingO-tracer oxidation experiments, and the composition and microstructure of the oxide scales were characterized by TEM and STEM. Segregation of Y cations at CrO grain boundaries was found to be the critical factor governing changes in the oxidation behavior of Cr upon the addition of Y. In the absence of Y, pure Cr oxidized by the outward diffusion of cations via grain boundaries in the CrO scale. When Y was present at high concentration in the scale, as when Cr implanted with 2×10 Y ions/cm was oxidized, anion diffusion predominated. It is concluded that strain-induced segregation of Y at grain boundaries in the oxide reduced the cation flux along the grain boundaries. The rate of oxidation was reduced because the grain-boundary diffusivity of cations became lower than the grain-boundary diffusivity of the anions, which then controlled the rate of oxidation. Changes in the relative rates of Cr and O transport, as well as a solute-drag effect exerted by Y on the oxide grain boundaries, resulted in changes in the microstructure of the oxide. [ABSTRACT FROM AUTHOR]

We have investigated the effect of Y ion implantation on the high-Temperature oxidation of Fe-24Cr using Rutherford-backscattering spectroscopy, secondary ion mass spectroscopy, and analytical electron microscopy. Results indicate that implantation of Y has a very large effect on the growth rate of the oxide compared to metals alloyed with Y. Analytical tools have been applied to determine the spatial distribution of Y, the microstructure of the oxide, and contribution of oxygen transport to the oxidation process. Results are compared with those of recent cation-diffusion measurements in CrO and CrO doped with YO. [ABSTRACT FROM AUTHOR]

We have carried our constant strain-rate compression tests on polycrystalline CrO and CrO doped with 0.09 wt. % YO to establish whether there exists an effect of YO on the plasticity of CrO. This study is motivated by previous work on the oxidation of alloys containing reactive-element additions. In that work, it has been observed that the addition of oxygen-active elements, such as Y to alloys that form CrO or AlO oxide layers upon exposure at high temperature, strongly enhances the adhesion of the oxide layer to the base alloy as compared with alloys without reactive-element additions. We have found that at 1200°C (1) chromia exhibits limited plasticity at high temperatures, and (2) the presence of Y in the oxides does not enhance plasticity compared with addition-free oxides. [ABSTRACT FROM AUTHOR]

Sulfur solubility in pure CrO was measured over a large range of oxygen (10−10 atm) and sulfur (10 -10 atm) partial pressures at 1273 K. Different methods of analysis were used; it was found that the neutronactivation technique produced the most reliable and reproducible results. The results obtained showed that the limiting solubility of sulfur in CrO varied between 16-93 ppm for the range of oxygen and sulfur pressures used in this study. The solubility was found to vary, depending on the combined effect of $$P_{O_2 } $$ and $$P_{S_2 } $$ . For a given $$P_{O_2 } $$ , the amount dissolved increases with an increase of $$P_{S_2 } $$ . An empirical equation, $$[S] = P_{O_2 }^{0.030} P_{S_2 }^{0.066} $$ was found to best fit the experimental results and indicates a stronger influence of $$P_{S_2 } $$ than of $$P_{O_2 } $$ . A specific dissolution mechanism connot be formulated from this equation. However, a number of possibilities have been proposed, but none of these specific mechanisms seems to fit the experimental data. [ABSTRACT FROM AUTHOR]

Currentunderstanding of the complex interrelationships among growth kinetics, microstructure, and adhesion of protective CrO and AlO scales is critically reviewed. Similarities and differences in the behavior of these two systems are highlighted. The morphology of the alloy-scale interface appears to be a critical factor. Recent ideas are advanced to interpret the effect of oxygen-active elements on the development of a tortuous interface conducive to improved scale tenacity. [ABSTRACT FROM AUTHOR]