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This work presents the Network Assisted Routing and Allocation Algorithm (NARA), a routing and allocation algorithm for device-to-device (D2D) communication in 5G cellular architectures. NARA algorithm is a new routing and resource block allocation algorithm that aims at reducing the impact of interference and extends network coverage in D2D communications. We model the allocation of resource blocks as a Minimum Graph Coloring Problem. As baselines, we compare the proposed strategy to NAR-G, a previous version that uses a greedy allocation heuristic; MaxC/I, a reference heuristic for resource allocation; and LBS-AOMDV for routing. The results reveal that NARA reduces message loss in 47.4% when compared LBS-AOMDV, 39.87% to NAR-G, and 23.06% when compared to MaxC/I. As for allocation, NARA provides 23.05% more D2D flows than MaxC/I.

Two-dimensional (2D) titanium disulfide (TiS 2) is the lightest transition-metal dichalcogenide (TMD). It exhibits relatively better adsorption and diffusion of sodium (Na) and potassium (K) ions than other TMDs, such as MoS 2 (molybdenum disulfide) and ReS 2 (rhenium disulfide), making it a promising anode material for alkali-ion batteries. Previous studies have found that doping significantly enhances the adsorption and diffusion capabilities of 2D TMDs. For the first time, this work reports the adsorption of Na and K ions on doped TiS 2 monolayers using first-principles calculations, where the Ti atom is substituted by 3d-transition metals, including iron (Fe), cobalt (Co), nickel (Ni), and copper (Cu). Metal-atom doping induces remarkably stronger binding of alkali ions on the surface of TiS 2 , with adsorption energies ranging from − 2.07 to − 2.48 eV for Na and − 2.59 to − 3.00 eV for K. The diffusion barrier energies for alkali ions decrease in the proximity of the doping site and increase as the ions travel away from the doping site for Fe-, Co-, and Ni-doped TiS 2. The average open circuit voltage increases dramatically when Na ions are adsorbed on Fe-doped TiS 2 (by 62%) and Co-doped TiS 2 (by 61%), while K ions result in a moderate improvement of 9% and 8%, respectively. These findings suggest that metal-atom doping considerably improves the electrochemical properties of 2D TiS 2 , potentially enabling its use as anode materials in Na- and K-ion batteries. [ABSTRACT FROM AUTHOR]

Presents a study that measured the lattice parameters and saturation magnetization for the series of intermetallic compounds zirconium, hafnium (iron, boron) and silicon, aluminum. Concentration of the compounds; Magnetization measurements; Parameter behavior of the compounds.

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Polymorphisms in the genomic DNA of eight varieties maintained by conventional bud propagation (via rhizomes) and by in vitro shoot tip cultures were detected by RAPD analysis of sugarcane varieties. The study estimated the genetic diversity induced after in vitro multiplication of these varieties. Higher (28.9%) and lower (12%) numbers of polymorphic bands were detected in plants propagated via rhizomes; the genetic similarity estimate varying from 0.63 to 0.80. Plants of SP90-3723 and SP91-1049, or RB85-5113 and SP90-3723, varieties involving greater genetic distances may be indicated as progenitors in breeding programmes. In vitro multiplication of RB86-7515, RB85-5113, RB83-5054 and SP86-42 varieties increases genetic variability, while in vitro multiplication of SP91-1049, SP90-1638, RB92-8064 and SP90-3723 leads to genetic similarity. Results show that the RAPD technique is an effective tool for detecting polymorphism in sugarcane clones and it allows quick collection of the necessary information (more genetically divergent plant varieties) to guide new crossing in sugarcane breeding programmes. [ABSTRACT FROM AUTHOR]

Background: The effects of Helicobacter pylori infection associated with inhibition of gastric acid secretion on the distribution of medications used for H. pylori eradication are poorly understood. The aim of this study was to investigate the effects of a 7-day administration of 20 mg omeprazole on the transfer of metronidazole from plasma to the gastric juice of individuals with and without H. pylori infection. Methods: Fourteen H. pylori-positive and 14 H. pylori-negative male volunteers were enrolled in a study with an open, randomized, two-period crossover design with a 21-day washout period between phases. Plasma, salivary, and gastric juice concentrations of metronidazole in subjects with and without omeprazole treatment were measured with reversed-phase high-performance liquid chromatography/liquid chromatography. Results: Metronidazole peak concentration (C[sub max]) was similar in plasma and saliva and was ≈ threefold higher in gastric juice in all groups. Omeprazole treatment increased gastric pH and did not affect metronidazole C[sub max] or the time required for this to be reached (t[sub max]) in plasma, saliva, or gastric juice. However, omeprazole significantly reduced metronidazole transfer from plasma to gastric juice in H. pylori-positive but not H. pylori-negative subjects, as shown by statistical analysis of AUC[sub 0-2 h]. Conclusion: Short-term treatment with omeprazole in H. pylori- positive volunteers reduces the amount of metronidazole transferred from plasma to gastric juice. This seems to occur in a pH-independent form. [ABSTRACT FROM AUTHOR]