RESUMEN
We report various phase transitions in half-Heusler TbPtBi compound using density functional theory. Specifically, the inclusion of spin-orbit coupling (SOC) leads to the band inversion resulting in the transition from the metallic to the topological semimetallic phase. However, in the presence of SOC, there is a phase transition from the topological semimetal to the trivial semimetal when the material is subjected to compressive strain-7%. Subsequently, under the further increase of compressive strain(⩾ââ-7%), we find an opening of a direct band gap at the point, driving the system from the trivial semimetallic to a semiconducting state with changes in the sequence of the bands. In the absence of SOC, only the transition from the metallic to the semiconducting phase is noticed. Under tensile strain, the TbPtBi compound maintains its phase as in the unstrained condition but with an increase in the hole pocket at the Fermi level, both in the absence and presence of SOC. These tunable phase transitions (especially as a fraction of strain) make this compound very promising for application in various quantum devices, such as highly sensitive strain gauges.
RESUMEN
We have applied the powerful self-consistent renormalization theory of spin fluctuations for the system CaMn2Al10discovered in 2015 and was conjectured to be an itinerant magnet. We have calculated the inverse static i.e. (paramagnetic) susceptibility and have compared it with the experimental data (Steinkeet al2015Phys. Rev.B92020413). The agreement is very good. We have calculated spin fluctuations at various temperatures and have also estimated the strength of the electronic correlation i.e. (U = 0.3136 eV) in the Hubbard Hamiltonian. Based on our quantitative explanation of the inverse static i.e. (paramagnetic) susceptibility data within the framework of self-consistent renormalization theory, we can decisively conclude CaMn2Al10exhibits the phenomena of itinerant magnetism. Further, our density functional theory (DFT) and DFT + U calculations corroborate the strong Mn-Al hybridization which is the key to the itinerant magnetism in this system. Our estimated correlations strength will provide a foundation for further studies of itinerant magnetism in this system.
RESUMEN
INTRODUCTION: Oral cancer is a major health problem and its early detection is advantageous for therapeutic purposes. According to available evidence, the risks of oral malignancies increase with the usage of tobacco and other psychoactive substances (PSs). The present study showed expression pattern of nuclear and cytoplasmic changes from normal individuals without habit to oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC) in PS abusers with the help of fluorescence acridine orange (AO) stain and Papanicolaou (PAP) stain. AIM AND OBJECTIVES: This study aimed to investigate and compare diagnostic efficacy of fluorescence microscopic evaluation of AO stain in cytological smears with PAP staining under light microscopy in PS abusers having oral potentially malignant and malignant lesions. MATERIALS AND METHODS: Oral smears from 120 individuals among which 40 from potentially malignant disorders, 40 from oral malignancy and 40 normal buccal mucosa smears were prepared. One set of smears was stained by AO staining and the other by PAP staining and examined under fluorescence and light microscope, respectively. The results of both the stainings were evaluated by grading cytology smears in class-I to class-V cytology. RESULTS: The AO fluorescence stain reliably demonstrated malignant cells based on the differential fluorescence. The efficacy of AO fluorescence stain was higher than PAP stain in screening of oral lesions suspicious of malignancy. The sensitivity of PAP staining and AO staining is 57.50% and 61.25%, respectively. CONCLUSION: As compared to PAP staining method, fluorescent AO method is more effective in screening of OPMD and OSCC in PS abusers.
