Characterization of highly-oriented ferroelectric Pb_xBa_(1-x)TiO_3

Pb_xBa_(1-x)TiO_3 (0.2 ≾ x ≾ 1) thin films were deposited on single-crystal MgO as well as amorphous Si_3N_4/Si substrates using biaxially textured MgO buffer templates, grown by ion beam-assisted deposition (IBAD). The ferroelectric films were stoichiometric and highly oriented, with only (001) and (100) orientations evident in x-ray diffraction (XRD) scans. Films on biaxially textured templates had smaller grains (60 nm average) than those deposited on single-crystal MgO (300 nm average). Electron backscatter diffraction (EBSD) has been used to study the microtexture on both types of substrates and the results were consistent with x-ray pole figures and transmission electron microscopy (TEM) micrographs that indicated the presence of 90° domain boundaries, twins, in films deposited on single-crystal MgO substrates. In contrast, films on biaxially textured substrates consisted of small single-domain grains that were either c or a oriented. The surface-sensitive EBSD technique was used to measure the tetragonal tilt angle as well as in-plane and out-of-plane texture. High-temperature x-ray diffraction (HTXRD) of films with 90° domain walls indicated large changes, as much as 60%, in the c and a domain fractions with temperature, while such changes were not observed for Pb_xBa_(1-x)TiO_3 (PBT) films on biaxially textured MgO/Si_3N_4/Si substrates, which lacked 90° domain boundaries

The Quark-Gluon Plasma Equation of State and The Generalized Uncertainty Principle

The quark-gluon plasma (QGP) equation of state within a minimal length scenario or Generalized Uncertainty Principle (GUP) is studied. The Generalized Uncertainty Principle is implemented on deriving the thermodynamics of ideal QGP at a vanishing chemical potential. We find a significant effect for the GUP term. The main features of QCD lattice results were quantitatively achieved in case of $n_{f}=0$, $n_{f}=2$ and $n_{f}=2+1$ flavors for the energy density, the pressure and the interaction measure. The exciting point is the large value of bag pressure especially in case of $n_{f}=2+1$ flavor which reflects the strong correlation between quarks in this bag which is already expected. One can notice that, the asymptotic behavior which is characterized by Stephan-Boltzmann limit would be satisfied.Comment: 9 Pages, 8 figure

Modified dome shaped proximal tibial osteotomy for treatment of infantile tibia vara

Background: Tibial deformity in childhood is not always one plane deformity, but often combines torsional and angular malalignment.Methods: In this prospective study, dome shaped osteotomy was performed in 36 tibiae in 24 patients. The osteotomy was held with K-wires and a plaster cast. The mean age at surgery was 5.5 years and the mean follow-up time was 30 months, range (24-42) months.Results: All osteotomies united and no compartment syndrome occurred. Postoperatively, one leg (2.7%) had temporary weakness of external hallucis longus muscle. Thirty five of thirty six legs had good clinical and radiological correction of alignment. Recurrent deformity was seen in one leg. ‎ Conclusions: Dome shaped osteotomy of the tibia is a simple, safe and effective method for correction of uni-planar varus deformity. For bi-planar deformities in childhood with infantile tibia vara we may need to step cut the lateral cortex to allow good bone contact to help in union with minimum morbidity.

Human Impacts on Coral Reef Ecosystem

Healthy, Coral reefs are the most spectacular, diverse and economically valuable marine ecosystems on the planet, Complex and productive, coral reefs are extremely important for biodiversity, providing a home to 35,000–60,000 species of plants and animals (over 25% of all marine life), many of which are not described by science. They are also vital for people and business. They provide nurseries for many species of commercially important fish, protection of coastal areas from storm waves. They are providing hundreds of billions of dollars in food, jobs and significant attraction for the tourism industry. Yet coral reef ecosystems have undergone phase shifts to alternate, degraded assemblages because of the combined human activates of unsustainable overfishing, intensive tourism, urbanization, sedimentation, declining water quality, pollution and primarily from the direct and indirect impacts of climate change. Most coral ecologists confirm that coral reef degradation has increased dramatically during the last three decades due to enhanced anthropogenic disturbances and their interaction with natural stressors. So, it is necessary to recognize the threats facing coral reefs from anthropogenic activities and try to minimize and mitigate these impacts

Physiological factors affecting the production of an antimicrobial substance by Streptomyces violatus in batch cultures

Egyptian Journal of Biology Vol.3 2001: 1-1

POSSIBLE PROTECTIVE ROLE OF SODIUM SALICYLATE NANOEMULSION AND GINGER ON CISPLATIN‑INDUCED HEPATOTOXICITY IN RATS (BIOCHEMICAL AND HISTOPATHOLOGICAL STUDY)

Objective: To describe the preparation and characterization of nanoemulsion of sodium salicylate loaded butane tetracarboxylic acid (Bt-Sc-NPs). It also investigates the possible protective effects of Bt-Sc-NPs and\or medicinal plant ginger to evaluate the changes of liver functions, oxidative stress and histopathological investigations against cisplatin-induced hepatotoxicity. Methods: Serum was used to determine alanine aminotransferase (ALT), aspartate aminotransferase (AST), δ-glutamyl transferase (δGT), serum human laminin (LN) and tissue inhibitors of metalloproteinase1 (TIMP1). Liver tissue samples collected from the rats were used for the measurement of malondialdehyde (MDA), nitric oxide (NO) and paraoxonase 1 (PON1). Results: The beneficial effects of Bt-Sc-NPs with its anti-inflammatory effect and the medicinal ginger with its antioxidant effect were observed. Injection of rats with cisplatin significantly increased serum ALT, AST, ɤGT, TIMP1 and LN. It also increased cisplatin-induced oxidative stress by a significant elevation in liver MDA, NO content; however, a significant decrease of PON1 content. While protection with Bt-Sc-NPs or ginger significantly improved these parameters. In addition, combination of both Bt-Sc-NPs and ginger significantly induced a decrease in serum ALT, AST, ɤGT, TIMP1 and LN. It also reduced cisplatin-induced oxidative stress by the significant reduction in liver MDA, NO content and elevation of PON1 content much more than protection with Bt-Sc-NPs or ginger alone. Conclusion: Bt-Sc-NPs were synthesized using nanoemulsion with the help of homogenization and ultra-sonication waves. Combination with both of Bt-Sc-NPs and ginger showed a hepatoprotective role in ameliorating cisplatin‑induced hepatotoxicity due to their anti-inflammatory and antioxidant effects