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The temperature dependent thermophysical, mechanical and ultrasonic properties of B2 structured ferromagnetic materials MTi (M: Fe, Co, Ni) have been evaluated in present study. The Coulomb and Born-Mayer potential model has been applied to calculate second and third order elastic constants in the temperature range 0-300K. The values of second order elastic constants have been used to find the mechanical and thermophysical properties. The chosen materials have been found ductile as the value of Pugh's indicator for MTi has been found greater than 1.75. The FeTi has been found more stable than CoTi and NiTi. The mechanical constants have been found highest for FeTi. Again, the values of elastic stiffness constants have been used to compute the ultrasonic velocities, Debye average velocities, Debye temperatures, thermal conductivities and Grüneisen parameters along <100>, <110> and <111> directions for the longitudinal and shear modes of wave propagation. The ultrasonic velocities have been observed more for longitudinal mode than shear mode. The ultrasonic velocities and Debye temperatures are found to be highest along <100> direction for all chosen materials. Hence <100> direction would be most suitable for the wave propagation in case of MTi. The obtained values of elastic, mechanical, thermophysical and ultrasonic properties have been compared with existing literatures and discussed. [ABSTRACT FROM AUTHOR]

The molecular underpinnings of metabolic adaptation to seasons are poorly understood in long- distance migrants. We measured changes in physiology and performed de novo sequencing of RNA extracted from liver samples collected at 4-h intervals over a period of 24 h from a long-distance avian migrant, the blackheaded bunting (Emberiza melanocephala), during two states: photostimulated vernal migratory (M) state and photorefractory non-migratory (nM) state. The M state was differentiated from the nM state based on body fattening and weight gain, as well as on Zugunruhe, that is, nocturnal migratory restlessness in caged birds. We found that baseline blood glucose and triglyceride levels were significantly higher in the M state than the nM state; conversely, surface body temperature was higher in the nM state than the M state. In a total of 6 liver samples that were sequenced from each state, 11,246 genes were annotated, including 4448 genes that were cyclic over 24 h. We found 569 differentially expressed genes (DEGs) between the M and the nM state, and the M state showed 131 upregulated and 438 downregulated genes. These DEGs formed core gene hubs associated with specific biological processes in both the states. In addition, weighted gene coexpression network analysis revealed two discrete modules of coexpressed genes, with a significant difference in the expression pattern of metab olism-associated genes between M and nM states. These results demonstrate, for the first time, transcriptome-wide changes in the liver between two distinct physiological states and give molecular insights into seasonal metabolic adaptations in latitudinal migrants.

This work explores the investigation of tin monochalcogenides i.e. SnX (X: S, Se, Te) at room temperature (300 K). The mechanical, thermophysical and ultrasonic properties of SnX (X: S, Se, Te) have been evaluated using the computed values of second- and third-order elastic constants (SOECs and TOECs). The SOECs and TOECs have been obtained using Born–Mayer potential model at 0 K and 300 K. The brittleness behavior of tin monochalcogenides is detected by Pugh's ratio. It is observed that phonon–phonon interaction mechanism is dominant in tin monochalcogenides leading to high ultrasonic attenuation. The obtained temperature dependence behavior of tin monochalcogenides is validated via comparison with available works of literature data in previous works done experimentally as well as theoretically by others. [ABSTRACT FROM AUTHOR]

The ultrasonic characteristics of dysprosium monochalcogenides, DyX (X = S, Se and Te) as a function of temperature and crystallographic direction, are studied in present investigation. First, the second- and third-order elastic constants (SOECs and TOECs) have been computed using Coulomb and Born-Mayer potential from 0K to 500K. The mechanical properties have been evaluated with the achieved values of SOECs for finding the intrinsic properties, stability and futuristic performance of DyX. The mechanical stability and elastic moduli follow the order DyS > DySe > DyTe. Supplemental the acoustic velocities including Debye average velocity, thermal relaxation time, Debye temperature and nonlinear parameter have been computed along <100>, <110> and <111> directions in the temperature range 100K to 500K. The Debye average velocity is found to be highest for wave propagating along <110> and polarized along <...0>. Finally, the ultrasonic attenuation using the modified Mason's approach has been computed in the temperature regime 100-500K along different crystallographic directions and calculated results predict that Akheiser damping dominates over the thermal attenuation. The obtained results have been analyzed and discussed with the available literature. [ABSTRACT FROM AUTHOR]

Genetically modified crops (GMCs) have emerged as a revolutionary force in agriculture, offering promising solutions to address global challenges such as food security, environmental sustainability, and economic viability. The overview of genetically modified crops, encompassing their development, benefits, concerns, and future prospects. Genetically modified crops are created through the incorporation of specific genes from one organism into another to confer desirable traits, such as resistance to pests, diseases, and environmental stresses, or enhanced nutritional profiles. The development of GMCs involves advanced biotechnological techniques, including gene editing tools like CRISPR-Cas9 and traditional methods like selective breeding. The benefits of genetically modified crops are multifaceted. Improved yield and crop resilience contribute to increased food production, addressing the growing global population's nutritional needs. Resistance to pests and diseases reduces the reliance on chemical pesticides, promoting environmentally friendly and sustainable agricultural practices. Additionally, some GMCs are designed to withstand harsh environmental conditions, such as drought or soil salinity, expanding the range of cultivable land. However, the widespread adoption of genetically modified crops has sparked debates and raised concerns. Environmentalists express apprehension about potential ecological impacts, including the unintentional spread of modified genes to wild plant populations and the development of resistance in target pests. Socioeconomic issues, such as intellectual property rights and corporate control over seeds, have also been contentious topics. To address these concerns, ongoing research focuses on refining the safety assessment protocols for genetically modified crops, implementing responsible and transparent regulatory frameworks, and conducting long-term environmental impact studies. Public awareness and engagement play a crucial role in shaping the ethical, legal, and social aspects surrounding genetically modified crops. Looking ahead, the future of genetically modified crops holds promise for addressing emerging challenges in agriculture. Continued advancements in gene editing technologies, increased understanding of plant genetics, and collaboration among scientists, policymakers, and communities can pave the way for innovative solutions. Striking a balance between harnessing the benefits of genetically modified crops and addressing ethical and environmental considerations will be paramount for realizing their full potential in global agriculture. [ABSTRACT FROM AUTHOR]

The elastic, mechanical, thermophysical and ultrasonic properties of platinum group metal (pgm) carbides XC (X = rhodium, palladium, iridium) have been investigated at room temperature. The Coulomb and Born-Mayer potential model was used to compute second- and third-order elastic constants (SOECs and TOECs) at 0 K and 300 K. The obtained values of SOECs were used to evaluate mechanical properties such as Young's modulus, bulk modulus, shear modulus, Pugh's indicator, Zener anisotropic constant and Poisson's ratio at room temperature. The materials show brittle nature as the value of Pugh's indicator for pgm carbides is =1.75. The values of SOECs were used to compute the ultrasonic velocities along <100>, <110> and <111> directions for the longitudinal and shear modes of wave propagation. Further, the values of Debye temperature, thermal conductivity, specific heat per unit volume, energy density, average value of ultrasonic Grüneisen parameter, thermal relaxation time and non-linear parameter were calculated with the help of SOECs, TOECs, ultrasonic velocities, density and molecular weight. Finally, the ultrasonic attenuation due to phononphonon interaction and due to thermoelastic relaxation mechanisms were calculated with the use of all associated parameters. The calculated values of elastic, mechanical, thermophysical and ultrasonic properties are compared with available literature and discussed. [ABSTRACT FROM AUTHOR]

The theoretical assessment of mechanical and elastic properties is used to analyze the distinctive properties of high entropy alloys (HEAs) at room temperature. Using Lennard–Jones potential model, the second order elastic constants (SOECs) and third order elastic constants (TOECs) have been determined for the HEAs Hf0.25Ti0.25Zr0.25Sc0.25−xAlx (x ≤ 15 %) in their hexagonal close-packed (hcp) phases. SOECs have been used to calculate mechanical constants, Poisson's ratio, Pugh's ratio, Kleinman's parameter. In order to determine the anisotropic behaviour of the selected HEAs, the elastic anisotropy has also been computed at room temperature. All the HEAs under consideration have anisotropy parameters that are not equal to one, indicating anisotropic behaviour. Later, the Grüneisen parameters were estimated for the chosen HEAs Hf0.25Ti0.25Zr0.25Sc0.25−xAlx (x ≤ 15 %) along longitudinal and shear modes of wave propagation. Analysis of the research results reveals the inherent properties of HEAs. [ABSTRACT FROM AUTHOR]

The temperature-dependent elastic and ultrasonic properties of curium monopnictides CmPn (Pn = N, P, As, Sb) have been explored in the present investigation. The second- and third-order elastic constants have been calculated using Coulomb and Born-Mayer potentials using lattice and hardness parameters. Mechanical parameters, such as Young's modulus, bulk modulus, shear modulus, tetragonal modulus, anisotropic factor, and Poisson's ratio, have been computed with second-order elastic constants. These materials fulfilled the requirement of the Born stability criterion. The toughness or fracture ratio is found to be more than 0.57 in CmPn, which indicates their brittle nature. In addition, the ultrasonic wave velocity, Debye average velocity, Debye temperature, thermal relaxation time, thermal conductivity, acoustic coupling constant, and ultrasonic attenuation have also been computed along (100), (110), (111) directions at room temperature. The results are discussed in correlation with other similar types of the materials. Key words: curium monopnictides, elastic constants, mechanical properties, ultrasonic properties, thermal conductivity. Dans cette etude, nous explorons les proprietes ultrasoniques et elastiques de mono-pnictures du curium, CmPn (Pn = N, P, AS, Sb). Utilisant le potentiel de Coulomb et Born-Mayer avec parametres de reseau et de durete, nous en calculons les constantes elastiques de deuxieme et de troisieme ordre. Nous calculons les parametres mecaniques comme le module de Young, le module d'elasticite volumique, le module de cisaillement, le module tetragonal, le facteur d'anisotropie et le rapport de Poisson, avec les constantes elastiques du deuxieme ordre. Ces materiaux remplissent les exigences du critere de stabilite de Born. Nous trouvons que le rapport de tenacite a la fracture est plus de 0.57 dans les CmPn, ce qui nous fournit de l'information sur leur fragilite. Nous calculons aussi la vitesse des ondes ultra-soniques, la vitesse moyenne de Debye, la temperature de Debye, le temps de relaxation thermique, la conductivite thermique, la constance de couplage acoustique et l'attenuation ultrasonique selon les directions (100), (110) et (111) a la temperature de la piece. Les resultats sont analyses en correlation avec d'autres types de materiaux similaires. [Traduit par la Redaction] Mots-cles: monopnictures de curium, constantes elastiques, proprietes mecaniques, proprietes ultrasoniques, conductivite thermique., Introduction The elastic and ultrasonic properties of materials have played a vital role in materials science and engineering for a long time, because of their numerous applications in every field [...]