Synthesis and characterization of polymeric linseed oil grafted methyl methacrylate or styrene

Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.% of peroxide, with molecular weights of 2100 and 3780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-linked part at the end of 24 d under visible irradation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styreine (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with M-w varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR. H-1 NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMNA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering

A Comparison of the LVDP and {\Lambda}CDM Cosmological Models

We compare the cosmological kinematics obtained via our law of linearly varying deceleration parameter (LVDP) with the kinematics obtained in the {\Lambda}CDM model. We show that the LVDP model is almost indistinguishable from the {\Lambda}CDM model up to the near future of our universe as far as the current observations are concerned, though their predictions differ tremendously into the far future.Comment: 6 pages, 5 figures, 1 table, matches the version to be published in International Journal of Theoretical Physic

Cosmological models with linearly varying deceleration parameter

We propose a new law for the deceleration parameter that varies linearly with time and covers Berman's law where it is constant. Our law not only allows one to generalize many exact solutions that were obtained assuming constant deceleration parameter, but also gives a better fit with data (from SNIa, BAO and CMB), particularly concerning the late time behavior of the universe. According to our law only the spatially closed and flat universes are allowed; in both cases the cosmological fluid we obtain exhibits quintom like behavior and the universe ends with a big-rip. This is a result consistent with recent cosmological observations.Comment: 12 pages, 7 figures; some typo corrections; to appear in International Journal of Theoretical Physic

The gradient flow running coupling with twisted boundary conditions

We study the gradient flow for Yang-Mills theories with twisted boundary conditions. The perturbative behavior of the energy density $\langle E(t)\rangle$ is used to define a running coupling at a scale given by the linear size of the finite volume box. We compute the non-perturbative running of the pure gauge $SU(2)$ coupling constant and conclude that the technique is well suited for further applications due to the relatively mild cutoff effects of the step scaling function and the high numerical precision that can be achieved in lattice simulations. We also comment on the inclusion of matter fields.Comment: 27 pages. LaTe

(Digital Presentation) Optimization of MIM Rectifiers for Terahertz Rectennas

Metal-Insulator-Metal (MIM) rectifiers comprising thin films of Al2O3, ZnO, NiO and Nb2O5 and metal configurations of Au/Au, Au/Zn and AuCr/AuCr, have been fabricated using atomic layer deposition and radio-frequency sputtering. The effect of device area scaling from 104 µm2 to 1 µm2 on rectification properties, in particular zero-bias dynamic resistance (R0) and zero-bias responsivity (β0) has been studied and found to be of critical importance in improving diode coupling efficiency. A significant increase of current has been found for Au/3.3 nm ZnO/Au diode when compared to the reference Au/3 nm Al2O3/Au diode, that resulted in obtaining the lowest R0 of 540 W for a device area of 104 µm2. The best performing device is found to be 1 µm2 AuCr/6.77 nm NiO/AuCr featuring (R0, b0) = (461 kW, 0.76 A/W) and a coupling efficiency of 1.5 ´ 10-5 %.</jats:p

Analysis of the FGF gene family provides insights into aquatic adaptation in cetaceans

Cetacean body structure and physiology exhibit dramatic adaptations to their aquatic environment. Fibroblast growth factors (FGFs) are a family of essential factors that regulate animal development and physiology; however, their role in cetacean evolution is not clearly understood. Here, we sequenced the fin whale genome and analysed FGFs from 8 cetaceans. FGF22, a hair follicle-enriched gene, exhibited pseudogenization, indicating that the function of this gene is no longer necessary in cetaceans that have lost most of their body hair. An evolutionary analysis revealed signatures of positive selection for FGF3 and FGF11, genes related to ear and tooth development and hypoxia, respectively. We found a D203G substitution in cetacean FGF9, which was predicted to affect FGF9 homodimerization, suggesting that this gene plays a role in the acquisition of rigid flippers for efficient manoeuvring. Cetaceans utilize low bone density as a buoyancy control mechanism, but the underlying genes are not known. We found that the expression of FGF23, a gene associated with reduced bone density, is greatly increased in the cetacean liver under hypoxic conditions, thus implicating FGF23 in low bone density in cetaceans. Altogether, our results provide novel insights into the roles of FGFs in cetacean adaptation to the aquatic environment.ope

Temperature Dependence of \eta and \eta^{\prime} Masses

We investigate the temperature dependence of \eta and \eta^{\prime} masses due to scatterings from thermal pions in a heat bath using the non-linear sigma model. We show that mass shifts of \eta and \eta^{\prime} and the shift in the mixing angle are negligible.Comment: Latex, 11 pages, 2 eps figures include

Gamma-Ray Protection Properties of Bismuth-Silicate Glasses Against Some Diagnostic Nuclear Medicine Radioisotopes: A Comprehensive Study

This study aimed to perform an investigation for the potential implementation of bismuth silicate glasses as novel shield equipment instead of ordinary shields in nuclear medicine facilities. Accordingly, a group of Bi2O3 reinforced silicate glass system were investigated and compared with ordinary shields in terms of their gamma-ray attenuation properties in diagnostic nuclear medicine radioisotope energies emitted from99mTc,111 In,67Ga,123 I,131 I,81mKr,201Tl,133Xe. Mass attenuation coefficient (µm) results for glass samples were calculated comparatively with the XCOM program and MCNPX code. The gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff ) were obtained in the diagnostic gamma ray energy range from 75 to 336 keV. To confirm the attenuation performance of superior sample, obtained results were extensively compared with ordinary shielding materials. According to the results obtained, BISI6 glass sample with the highest Bi2O3 additive has an excellent gamma-ray protection. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This research was funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding Program

Engineering Multi-Agent Systems: State of Affairs and the Road Ahead

The continuous integration of software-intensive systems together with the ever-increasing computing power offer a breeding ground for intelligent agents and multi-agent systems (MAS) more than ever before. Over the past two decades, a wide variety of languages, models, techniques and methodologies have been proposed to engineer agents and MAS. Despite this substantial body of knowledge and expertise, the systematic engineering of large-scale and open MAS still poses many challenges. Researchers and engineers still face fundamental questions regarding theories, architectures, languages, processes, and platforms for designing, implementing, running, maintaining, and evolving MAS. This paper reports on the results of the 6th International Workshop on Engineering Multi-Agent Systems (EMAS 2018, 14th-15th of July, 2018, Stockholm, Sweden), where participants discussed the issues above focusing on the state of affairs and the road ahead for researchers and engineers in this area