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The transport behavior in a in LaVO3 Mott–Hubbard system is controlled by the degree of hybridization of the V 3d and O 2p states in the pure and doped systems, strongly associated with structural distortion.

We report a comparative study of the electronic structure and magnetic properties of two cobalt compounds Co3O4 and Co3S4, through first-principles Hubbard-U calculations. Our results indicate that Co3O4 and Co3S4 have similarities in crystal structure (normal spinel), magnetic order (antiferromagnetism), Co spin configuration (high spin Co2+ and low spin Co3+), and comparable band-gap energy. However, the U-dependence on electronic structure in two materials are different from each other. With a change in the applied U values, the band dispersion and the type of band gap are significantly changed in Co3O4, while the band-gap energy only is affected in Co3S4.

Antibiotic-resistant infections are a growing problem; to combat multi-drug resistant bacterial infections, antibiotics with novel mechanisms of action are needed. Identification of potent bioactive natural products is an attractive avenue for developing novel therapeutic strategies against bacterial infections. As part of our ongoing research to explore bioactive natural products from diverse resources, we investigated the antimicrobial compounds from Woodfordia uniflora, a flowering shrub unique to the Dhofar region of Oman. The plant has been used as a remedy for skin infections in Oman. However, to date, no study has examined the antimicrobial compounds in W. uniflora. Phytochemical analysis of the methanolic extract of W. uniflora leaves in combination with LC/MS-based analysis allowed us to isolate and identify four flavonoid-type analogs (1–4), procyanidin B3-3-O-gallate (1), rhamnetin 3-O-(6″-galloyl)-β-D-glucopyranoside (2), rhamnetin 3-O-α-L-rhamnopyranoside (3), and quercetin 3-O-(6″-galloyl)-β-D-glucopyranoside (4). The isolates have a novel mechanism of action; the compounds inhibit biofilm formation in methicillin-resistant Staphylococcus aureus (MRSA) and synergize with methicillin. Our metabolite analysis revealed that this synergizing activity by compounds was achieved by remodeling metabolism including central carbon metabolism and glutamine biosynthesis that resulted in abnormal cell formation and reduction in biofilm formation of MRSA. Taken together, these findings provide experimental evidence that rhamnetin 3-O-(6″-galloyl)-β-D-glucopyranoside (2) and quercetin 3-O-(6″-galloyl)-β-D-glucopyranoside (4) can be considered as potential therapeutic agents for the treatment of methicillin-resistant S. aureus-associated diseases.

We address the anisotropic oxygen diffusion in PrBaCo2O5.5 using first-principles calculations based on the density functional theory. First, the experimentally observed magnetic properties such as...

In this study, complete chloroplast genome sequences of Rhus chinensis was characterized by de novo assembly using whole genome sequence data. The chloroplast genome of R. chinensis were 149,011bp long, which was comprised of a large single copy region of 96,882 bp, a small single copy region of 18,647bp, and a pair of inverted repeats of 16,741 bp. The genome contained 77 protein-coding genes, four rRNA genes and 30 tRNA genes. Phylogenetic tree revealed that R. chinensis was closely grouped with Spondias species, S. tuberosa and S. bahiensis, belonging to the Anacardiaceae family.

Cucumber (Cucumis sativus var. sativus) is one of the economically important vegetable crops. In this study, we characterized the complete chloroplast genome sequence of inbred line ID YHB bred from Korean solid green-type cucumber variety, through de novo assembly using next-generation sequencing. The chloroplast genome is 155,501 bp long and has typical quadripartite structures and gene contents as found in reported cucumber chloroplast genomes. Interestingly, sequence comparison revealed a novel 24-bp deletion present only in the chloroplast genome of the inbred line. Phylogenetic analysis confirmed that the inbred line was closely grouped with cucumber cultivars.

Atomistic defect engineering through the pulsed laser epitaxy of perovskite transition metal oxides offers facile control of their emergent opto-electromagnetic and energy properties. Among the various perovskite oxides, EuTiO3 exhibits a strong coupling between the lattice, electronic, and magnetic degrees of freedom. This coupling is highly susceptible to atomistic defects. In this study, we investigated the magnetic phase of EuTiO$_3$ epitaxial thin films via systematic defect engineering. A magnetic phase transition from an antiferromagnet to a ferromagnet was observed when the unit cell volume of EuTiO3 expanded due to the introduction of Eu-O vacancies. Optical spectroscopy and density functional theory calculations show that the change in the electronic structure as the ferromagnetic phase emerges can be attributed to the weakened Eu-Ti-Eu super-exchange interaction and the developed ferromagnetic Eu-O-Eu interaction. Facile defect engineering in EuTiO$_3$ thin films facilitates understanding and tailoring of their magnetic ground state.

We perform first-principles calculations to investigate a two-dimensional 1T phase of $\mathrm{Ti}{\mathrm{O}}_{2}$. Our results indicate that electronic band gap, electron and hole effective mass, and structural stability of an 1T phase are comparable to those of bulk and the other two-dimensional phases. 1T-$\mathrm{Ti}{\mathrm{O}}_{2}$ is predicted to be easily achieved by exfoliation from bulk hexagonal ${\mathrm{NaTiO}}_{2}$, and the obtained phase is dynamically stable. In addition, we find that mechanical strain significantly influences the electronic structure of 1T-$\mathrm{Ti}{\mathrm{O}}_{2}$, and even it causes a transition from indirect to direct band gap.

In this study, complete chloroplast genome sequences of Rhus chinensis was characterized by de novo assembly using whole genome sequence data. The chloroplast genome of R. chinensis were 149,011bp long, which was comprised of a large single copy region of 96,882 bp, a small single copy region of 18,647bp, and a pair of inverted repeats of 16,741 bp. The genome contained 77 protein-coding genes, four rRNA genes and 30 tRNA genes. Phylogenetic tree revealed that R. chinensis was closely grouped with Spondias species, S. tuberosa and S. bahiensis, belonging to the Anacardiaceae family.

Purpose: Dosimetric characteristics of new P‐32 ophthalmic applicator as substitute for Sr/Y‐90 irradiation were evaluated. The integrity and safety were confirmed. The feasibility for 32P ophthalmic applicators was evaluated. Method and Materials:According to optimal design of P‐32 ophthalmic applicator, Monte Carlo simulations were performed to calculate dosimetric characteristics: reference dose rate, central axis depth doses, transaxial dose profiles. The reference dose rate at the surface of an ophthalmic applicator is measured by using an extrapolation ionization chamber (EC) and radiochromic film (RCF). Depth dose distributions and dose profiles were measured using RCF. The source non‐uniformity was calculated. The source leakage was examined for the safety. The effective shielding of the applicator was verified. Results: The reference dose rates of EC, RCF was 4.13 ± 0.21 cGy/s and 3.84 ± 0.25 cGy/s, respectively. The axial depth dose rate was reduced into approximately 1/10 as 32P betas penetrate every 2 mm depth. Measured data sets in depths of 1 mm to 3 mm agreed with Monte Carlo data. The dose profiles were not uniform due to non‐uniform activity distribution. At the surface (depth=0.1 mm), source non‐uniformities were 27.8%, 11.3% for film, MCNP, respectively. The exposure rate of the handle grip toward a clinician was 1.4 mR/hour (background: 0.1mR/hour). Conclusion: The 32P applicator with a 20 mCi (740 MBq) activity can deliver the therapeutic doses to the surface of the conjunctiva within 6 min, while sparing the lens better than 90Sr/Y applicators. The integrity and safety of an new P‐32 applicator was confirmed. However, prior to the clinical application of every new applicator, safety, dose uniformity, and absorbed dose rate at the reference point should be carefully evaluated by the method developed in this study.

Purpose: A device to modulate photon energy during beam‐on time was designed and simulated with the Monte Carlo(MC) method. Method and Materials:A device named energy modulator was a cylinder made of aluminum. The frame of that device was connected with 20 tubes through which mercury could be injected or drained. The mercury thickness inside the device could modulate the photon energy of beam penetrated. Monte Carlo simulations of 6 and 10 MV linac using the EGSnrc code were conducted to evaluate the performance of the device. After the design study, a flattening filter of the linac was replaced with the energy modulator in the MC simulations. At least 5 billion histories were followed for each simulation to create phase‐space files at 100 cm SSD. The thickness of mercury inside the energy modulator varied from 2 mm to 40 mm at the field size of 10 cm by 10 cm. The changes of beam quality were expressed in terms of percentage depth dose (PDD) at the depth of 10 cm and 20 cm in water. Results: As increasing the thickness of mercury, the PDD of 6 MV beam at 10 cm and 20 cm was changed from 63.8% to 68.2% and from 34.5% to 40.2%, respectively. The PDD of 10 MV beam was changed from 68.7% to 73.1% at the depth of 10 cm and 40.2% to 45.7% at the depth of 20 cm. Conclusions: The results of this study showed the feasibility of the energy modulation during beam‐on time, which could be advantageous in dose conformity.