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During the past few years, the researchers are focusing more on molecular tools to verify the data generated from the traditional research in aquaculture. Molecular tools help us to understand the metabolic response of the fish to a particular feed, ingredient, medicine, drugs or any other metabolic pathway etc of a particular species. Fish is one of the major sources of essential fatty acid like EPA and DHA. Two important enzyme Δ5 and Δ6 fatty acid desaturase and elongases are critical enzymes for the synthesis of highly unsaturated fatty acid. In this present study, investigate the Amplification of D6 desaturase gene from liver tissue of Cirrhinus mrigala. [ABSTRACT FROM AUTHOR]

We have investigated the non-commutativity of the band offset in RF magnetron sputter deposited all oxide epitaxial α-Cr2O3/β-Ga2O3 heterojunction (HJ). The core-level x-ray photoelectron spectroscopy technique has been employed to probe the electronic structure of the interface formed between α-Cr2O3 and β-Ga2O3. Valence and conduction band offsets of 2.6 ± 0.2 and 0.9 ± 0.2 eV, respectively, for α-Cr2O3/β-Ga2O3 HJ have been determined from Kraut's method. These values are different from those reported for β-Ga2O3/α-Cr2O3 HJ, thus indicating that the α-Cr2O3/β-Ga2O3 HJ does not follow the band commutativity with respect to the growth sequence of the constituting layers forming the HJ. Furthermore, the band alignment at α-Cr2O3/β-Ga2O3 HJ is still type-II like β-Ga2O3/α-Cr2O3 HJ but with lower band offset values. Therefore, this HJ would also be able to confine the electrons and holes in β-Ga2O3 and α-Cr2O3 layers, respectively, with lower turn on voltage. [ABSTRACT FROM AUTHOR]

Bonding characteristics of the β-(AlxGa1−x)2O3 alloy have been assessed from red luminescence and x-ray absorption near edge spectroscopy (XANES). Red luminescence, known as R1 and R2 lines, originates from crystal field split d-levels of unintentionally present Cr3+ ions in the β-(AlxGa1−x)2O3 alloy, is found to blueshift with Al composition. This indicates that the nephelauxetic effect in β-Ga2O3 materials decreases with Al substitution, which results to a decrease in the covalency of the β-(AlxGa1−x)2O3 alloy. The XANES experiments at the oxygen K-absorption edge provide clear evidence of the decrease in the covalency of the alloy, where an absorption peak representing the covalency in the β-Ga2O3 material is found to decrease with an increase in the Al composition. Furthermore, the nature of the observed red luminescence for the β-(AlxGa1−x)2O3 alloy is determined to be excitonic recombination. Our results further confirm the fact that the red luminescence from Cr3+ ions is an excellent local probe to assess the bonding characteristic of the host material. [ABSTRACT FROM AUTHOR]

Raman spectroscopy has been used to investigate the phonon mode behavior of a β-(AlxGa1−x)2O3 alloy up to Al compositions of x = 0.474. The alloy displays a mixed-mode behavior, where low frequency (100–200 cm−1) modes corresponding to translation and libration of (Ga1O4) tetrahedral and (Ga2O6) octahedral chains and high frequency (500–800 cm−1) modes related to stretching and bending of (Ga1O4) tetrahedral chains show a monotonic behavior throughout the studied composition range, and display one-mode behavior. On the other hand, medium frequency (300–500 cm−1) phonon modes related to the deformation of (Ga2O6) octahedra and (Ga1O4) tetrahedra chains show sudden change such as the appearance (disappearance) of new (existing) phonon modes corresponding to Al–O (Ga–O) sublattices with Al substitution, and they display a two-mode behavior. The existence of two sublattices is further supported by the observation of preferential occupation of the Al atom at the octahedral atomic site in comparison to the tetrahedral atomic site. The observation of phonon modes related to translation and libration of (Ga1O4) tetrahedral and (Ga2O6) octahedral chains up to the Al composition of x = 0.474 clearly indicates that the long-range periodicity of the monoclinic lattice is maintained throughout the investigated Al composition range. Our results provide an insight into the phonon mode behavior of β-(AlxGa1−x)2O3 alloys, which is necessary to have a better understanding of their physical properties. [ABSTRACT FROM AUTHOR]

Therefore, a major claim of the published article,[1] i.e., a sizable number of tetrahedral (T SB d sb ) atomic sites are filled by Al atoms even for lower Al compositions along with octahedral (O SB h sb ) atomic sites, and O SB h sb atomic site is preferred by Al atoms in the investigated composition range, is still valid. The Al composition (x) was inadvertently defined as the ratio of the number of Al atoms to the number of Ga atoms, i.e., x = number of Al atoms/number of Ga atoms. However, a sizable number of T SB d sb atomic sites, i.e., 20% for the Al composition of 4.8%, remains occupied by Al atoms, which is found to increase sharply with the Al composition. Thereafter, tiny amounts of 0.4% and 1% of the secondary phase of I i -Al SB 2 sb O SB 3 sb start appearing for the Al composition (x) of 47.4% and 48.7%, respectively, for I i -(Al SB x sb Ga SB 1-x sb ) SB 2 sb O SB 3 sb alloys. [Extracted from the article]