Effects of divalent dopants on the microstructure and conversion efficiency of Cr4+ ions in Cr,Me:YAG (Me – Ca, Mg, Ca/Mg) transparent ceramics

The efficiency of Cr4+:YAG is directly proportional to the transparency and concentration of Cr4+ which can be tuned by changing the divalent dopant. The aim of this study was to investigate the influence of different kinds of divalent dopants on the properties of Cr,Me:YAG (Me = Ca, Mg or Ca/Mg) ceramics made by solid-state sintering in vacuum. Pure YAG phases with an in-line transmittance of 80% at 1064nm were prepared. It was revealed that the Cr4+ concentration is directly proportional to the concentration of divalent dopants and it does not depend on the type of dopant. Our experiment proves that the efficiency of high optical quality Cr4+:YAG ceramics preparedby sintering does not change when different kinds of divalent additives are used

Games on graphs with a public signal monitoring

We study pure Nash equilibria in games on graphs with an imperfect monitoring based on a public signal. In such games, deviations and players responsible for those deviations can be hard to detect and track. We propose a generic epistemic game abstraction, which conveniently allows to represent the knowledge of the players about these deviations, and give a characterization of Nash equilibria in terms of winning strategies in the abstraction. We then use the abstraction to develop algorithms for some payoff functions.Comment: 28 page

Power provides protection : genetic robustness in yeast depends on the capacity to generate energy

The functional basis of genetic robustness, the ability of organisms to suppress the effects of mutations, remains incompletely understood. We exposed a set of 15 strains of Saccharomyces cerevisiae form diverse environments to increasing doses of the chemical mutagen EMS. The number of the resulting random mutations was similar for all tested strains. However, there were differences in immediate mortality after the mutagenic treatment and in defective growth of survivors. An analysis of gene expression revealed that immediate mortality was lowest in strains with lowest expression of transmembrane proteins, which are rich in thiol groups and thus vulnerable to EMS. A signal of genuine genetic robustness was detected for the other trait, the ability to grow well despite bearing non-lethal mutations. Increased tolerance of such mutations correlated with high expression of genes responsible for the oxidative energy metabolism, suggesting that the negative effect of mutations can be buffered if enough energy is available. We confirmed this finding in three additional tests of the ability to grow on (i) fermentable or non-fermentable sources of carbon, (ii) under chemical inhibition of the electron transport chain and (iii) during overexpression of its key component, cytochrome c. Our results add the capacity to generate energy as a general mechanism of genetic robustness

Implementation and evaluation of a transit dosimetry system for treatment verification

PURPOSE: To evaluate a formalism for transit dosimetry using a phantom study and prospectively evaluate the protocol on a patient population undergoing 3D conformal radiotherapy. METHODS: Amorphous silicon EPIDs were calibrated for dose and used to acquire images of delivered fields. The measured EPID dose map was back-projected using the planning CT images to calculate dose at pre-specified points within the patient using commercially available software, EPIgray (DOSIsoft, France). This software compared computed back-projected dose with treatment planning system dose. A series of tests were performed on solid water phantoms (linearity, field size effects, off-axis effects). 37 patients were enrolled in the prospective study. RESULTS: The EPID dose response was stable and linear with dose. For all tested field sizes the agreement was good between EPID-derived and treatment planning system dose in the central axis, with performance stability up to a measured depth of 18cm (agreement within -0.5% at 10cm depth on the central axis and within -1.4% at 2cm off-axis). 126 transit images were analysed of 37 3D-conformal patients. Patient results demonstrated the potential of EPIgray with 91% of all delivered fields achieved the initial set tolerance level of ΔD of 0±5-cGy or %ΔD of 0±5%. CONCLUSIONS: The in vivo dose verification method was simple to implement, with very few commissioning measurements needed. The system required no extra dose to the patient, and importantly was able to detect patient position errors that impacted on dose delivery in two of cases

Magnetic Phase Diagram of GdNi2B2C: Two-ion Magnetoelasticity and Anisotropic Exchange Couplings

Extensive magnetization and magnetostriction measurements were carried out on a single crystal of GdNi2B2C along the main tetragonal axes. Within the paramagnetic phase, the magnetic and strain susceptibilities revealed a weak anisotropy in the exchange couplings and two-ion tetragonal-preserving alpha-strain modes. Within the ordered phase, magnetization and magnetostriction revealed a relatively strong orthorhombic distortion mode and rich field-temperature phase diagrams. For H//(100) phase diagram, three field-induced transformations were observed, namely, at: Hd(T), related to the domain alignment; Hr(T), associated with reorientation of the moment towards the c-axis; and Hs(T), defining the saturation process wherein the exchange field is completely counterbalanced. On the other hand, For H//(001) phase diagram, only two field-induced transformations were observed, namely at: Hr(T) and Hs(T). For both phase diagrams, Hs(T) follows the relation Hs[1-(T/Tn)^2]^(1/2)kOe with Hs(T-->0)=128.5(5) kOe and Tn(H=0)=19.5 K. In contrast, the thermal evolution of Hr(T) along the c-axis (much simpler than along the a-axis) follows the relation Hr[1-T/Tr]^(1/3) kOe where Hr(T-->0)=33.5(5) kOe and Tr(H=0)=13.5 K. It is emphasized that the magnetoelastic interaction and the anisotropic exchange coupling are important perturbations and therefore should be explicitly considered if a complete analysis of the magnetic properties of the borocarbides is desired

Platelet‐Derived Growth Factor (PDGF) Gene Delivery for Application in Periodontal Tissue Engineering

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141045/1/jper0815.pd

Impact of Alkali Ions Codoping on Magnetic Properties of La(0.9)A(0.1)Mn(0.9)Co(0.1)O(3) (A: Li, K, Na) Powders and Ceramics

The aim of the work was to check how the introduction of alkali and cobalt ions into a manganese structure can affect the structural disorder and, in consequence, lead to the changes (improvements) of magnetic properties. The high-pressure sintering technique was applied to check if the external factor can modify the magnetization of manganites. Nanocrystalline La0.9A0.1Mn0.9Co0.1O3 (where A is Li, K, Na) powders were synthesized by the combustion technique. The respective powders were used for nanoceramics preparation by the high-pressure sintering technique. The structure and morphology of the compounds were studied by X-ray powder diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Magnetization studies for all compounds were performed in order to check the changes induced by either codoping or the sintering pressure. It was found that the type of the dopant ion and sintering pressure produced significant changes to the magnetic properties of the studied compounds. Alkali ions lead to the stabilization of Co ions in the +2 oxidation state and the formation of positive exchange interactions Mn3+–Mn4+ and Co2+–Mn4+ and the subsequent increase in remanent magnetization. High sintering pressure leads to a decrease in grain size and reduction of long-range ferromagnetic order and lower magnetization. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska‐Curie grant agreement No 778070–TransFerr–H2020‐MSCA‐RISE‐ 2017. Part of this work was developed within the scope of the project CICECO‐Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The equipment of the Ural Center for Shared Use “Modern nanotechnology” UrFU was used. The work has been supported in part by the Ministry of Science and Higher Education of the Russian Federation under Project № FEUZ‐2020‐0054

The effect of extrinsic mortality on genome size evolution in prokaryotes

Mortality has a significant role in prokaryotic ecology and evolution, yet the impact of variations in extrinsic mortality on prokaryotic genome evolution has received little attention. We used both mathematical and agent-based models to reveal how variations in extrinsic mortality affect prokaryotic genome evolution. Our results suggest that the genome size of bacteria increases with increased mortality. A high extrinsic mortality increases the pool of free resources and shortens life expectancy, which selects for faster reproduction, a phenotype we called ‘scramblers’. This phenotype is realised by the expansion of gene families involved in nutrient acquisition and metabolism. In contrast, a low mortality rate increases an individual’s life expectancy, which results in natural selection favouring tolerance to starvation when conditions are unfavourable. This leads to the evolution of small, streamlined genomes (‘stayers’). Our models predict that large genomes, gene family expansion and horizontal gene transfer should be observed in prokaryotes occupying ecosystems exposed to high abiotic stress, as well as those under strong predator- and/or pathogen-mediated selection. A comparison of genome size of cyanobacteria in relatively stable marine versus more turbulent freshwater environments corroborates our predictions, although other factors between these environments could also be responsible

Phytochemical composition and antioxidant capacity of the aqueous extracts of Malva sylvestris L. and Malva pseudolavatera Webb & Berthel.

Context: Malva spp. have been widely used in the world as traditional remedies. In Ecuadorian markers Malva sylvestris and Malva pseudolavatera are the species most commercialized. However, the scientific information about M. pseudolavatera is little. Aims: To determine the chemical composition and antioxidant capacity of the aqueous extracts of the leaves of both species. Methods: Aqueous extracts were partitioned with butanol and the fractions obtained were analyzed by GC/MS. Total extracts were evaluated as antioxidants using FRAP, DPPH and ABTS assays. Results: Differences in the chemical composition were found between the extracts. Both extracts showed the presence of polysaccharides, phenolic acids and fatty acids, but in M. sylvestris were identified polyols, which there was not observed in M. pseudolavatera. The aqueous extracts showed free radical scavenging and ferric reducing power capacities in vitro assays, being M. sylvestris the most promissory antioxidant, possibly due to the presence of polyols in the extract. In the present research were reported 39 phytochemical compounds by first time for the specie M. pseudolavatera. Conclusions: Aqueous extracts of the leaves of M. sylvestris and M. pseudolavatera showed antioxidant capacity associated with the presence of phenolic acids, polysaccharides and flavonoids in the extracts. Keywords: antioxidant; gas chromatography; Malva pseudolavatera; Malva sylvestris; phytochemicals